Avionics Test Bed Aircrafts

[Asterion Moloc]

I am creating this thread specifically for discussion and updates on Avionics related test bed aircrafts from around the world with most of the focus on military avionics. Feel free to contribute

• Boeing 757 F-22's Catfish

Members of the F-22 Flying Test Bed team pose for a photo in front of the highly modified Boeing 757, 3rd May 2017. The FTB routinely flies with real Raptors both at Edwards and Nellis Air Force Base, Nevada in order to gain an early look at F-22 mission software before the software is released to developmental flight test, mainly at Edwards. The FTB can fly up to 30 crewmembers. (U.S. Air Force photo by Ethan Wagner)

EDWARDS AIR FORCE BASE, Calif. --
From time to time, the F-22 Raptor Combined Test Force at the 411th Flight Test Squadron gets a visit from an old friend.


A highly modified and instrumented Boeing 757 called the F-22 Flying Test Bed is an F-22 avionics laboratory. The experimental FTB is the very first Boeing 757 ever produced and has been retrofitted in order to perform flight test of F-22 avionics and sensors in an open-air, operationally representative environment.


The FTB routinely flies with real F-22 Raptors both at Edwards and Nellis Air Force Base, Nevada in order to gain an early look at F-22 mission software before the software is released to developmental flight testers, mainly at Edwards.


The FTB visited earlier in the month to examine the F-22 Raptor program’s upgraded mission software.


“This particular FTB deployment provided an excellent training opportunity for the FTB test team, as well as members of the F-22 CTF, while reducing risk to the F-22 3.2B (software) program by allowing us to have an early look at some prototype mission software planned for the final 3.2B software delivery,” said Rachel Kitzmann, Boeing Agile Integration Laboratory F-22 lead test director. “Our F-22 mission equipment is completely segregated from the 757 flight controls, so we can fly with prototype software that has not gone through a formal Equipment Operational Flight Clearance process. This allows us to have an early look at developmental software and problem fixes prior to release to the 411 Flight Test Squadron here at Edwards.”


Kitzmann added the FTB has the ability to change software loads real-time during flight, which allows the test team to test multiple configurations during early developmental testing. The fact that all of the mission equipment is housed in a 757 means that Boeing test engineers, F-22 test pilots and other F-22 customer representatives can be present on board and witness the flight test in real time. Additionally, the 757 can fly approximately a seven-hour sortie, which is far longer than a typical F-22 flight test mission, she said.


“The FTB saves money and reduces the F-22 modernization timeline,” said Kevin Sullivan, 411th FLTS F-22 avionics lead. “It provides risk reduction because it’s easier to fly, fix, fly more quickly instead of having software certified and loaded into an actual F-22. It allows us to look at the avionics software in an F-22 representative hardware and software environment and is capable of acting like an F-22, which can integrate with our F-22s here during test sorties.”


When not in flight, the FTB is connected to Boeing’s Agile Integration Ground Laboratory, which allows the company to add additional hardware, instrumentation and test equipment in order to perform system-level integration and development testing of the F-22 mission systems. The F-22 FTB has a unique wing above the flight deck that houses the same sensors as on a Raptor.

More on F-22 Catfish

Kitzmann said this last mission to Edwards was the final flight the FTB took out of Boeing Field in Washington where it had been based since 1999. After leaving Edwards May 5, the FTB headed to its new home in St. Louis, Missouri.

https://www.edwards.af.mil/News/Article/1192651/f-22-flying-test-bed-is-tip-of-the-spear-for-raptor-mission-systems/

The Catfish’s current job in support of the F-22’s sensor suite is reflected in the Raptor nose grafted onto the forward fuselage, containing the AN/APG-77 active electronically scanned array (AESA) radar. A swept-wing section atop the flight deck houses conformal antennas for the Raptor’s AN/ALR-94 electronic support measures suite.

Less obvious is the Catfish’s use as a test platform for the F-22’s electronic warfare suite, low probability of intercept datalink, AN/AAR-56 IR/UV missile approach warning system, secure communications systems, and various other tactical subsystems.

Inside the cabin of the 757 are computer workstations, server racks, and even a replica of the F-22 cockpit, with primary and secondary displays, as well as a throttle and stick, providing the highest level of realism for testing, including recreating the kinds of tactical and environmental scenarios that F-22 pilots would be exposed to in real life. Altogether, there is room on the aircraft for up to 30 software engineers and technicians to evaluate the avionics during testing.

Boeing’s 757 ‘Catfish’ Flying F-22 Avionics Testbed Emerges With Retro Look

Retro colors recall that the famous Catfish began life as the very first of Boeing’s 757 narrow-body airliners. Retro colors recall that the famous Catfish began life as the very first of Boeing’s 757 narrow-body airliners.

www.twz.com

• Boeing 737-330 F-35's Cooperative Avionics Test Bed; CATBIRD

Source: Design of the Lockheed Martin Cooperative AvionicsTestbed, AIAA 2008-157
Robert Lind, James H. Hogue and Ian J. Gilchrist

https://arc.aiaa.org/doi/pdf/10.2514/6.2008-157

more images at <title>F-35 CATBird | Code One Magazine</title>

https://twitter.com/x/status/1749506341326954750

A Look At Lockheed Martin's 'CATBird' Boeing 737 Testbed

The CATBird performed its first flight in January 2007.

simpleflying.com

• Tupolev Tu-204-120CE for J-20's Catfish

China’s J-20 avionics testbed seen at the Yanglian flight test center (Yan liang, in Xi’an, covers an area of 244.4km2 and has a population of 240000. Xi’an Aircraft Industry (Group) Company, Ltd)

China’s Own “Catfish” Flying Avionics Testbed For The J-20 Fighter Emerges​

Tyler Rogoway
Updated Jul 5, 2020 6:56 PM EDT
China’s heavy stealth fighter-interceptor, the J-20, has rapidly matured over the last half decade, with some reports stating the jet may have reached limited initial operating capability. That term can mean very different things in the Russian and Chinese aerospace and defense communities than it does to their western counterparts. Fielding hardware early on, with minimal capabilities, and developing it in a spiral manner over time by using the operational community as a kind of testing ground, invites higher risk and less than fully vetted capabilities to front-line units. Yet it also offers more immediate results and can be strategically important not just in terms of fielded new capabilities, but also in terms of “optics” both for internal and external consumption.

Regardless of its operational state, the J-20 concept represents a potential threat as it was designed—along with other emerging Chinese aerial weaponry—to exploit weaknesses in American forces’ order of battle and combat doctrine. But the jet also represents a massive leap in Chinese aerospace and manufacturing capabilities and still holds many mysteries—maybe the most pressing among them is the maturity and intended abilities of its integrated avionics suite.

Now an image has emerged that shows how the Chinese are grabbing yet another play right out of modern western fighter development—using a surrogate airliner to act as a flying integrated avionics testbed for their new 5th generation fighter

China’s Own “Catfish” Flying Avionics Testbed For The J-20 Fighter Emerges

Lifting a play from western 5th generation fighter development methodology, China is facing its own challenges with 5th-gen fighter sensor fusion in the air.

www.twz.com

Apparently transferred to PLAAF in 2011

China’s Own “Catfish” Flying Avionics Testbed For The J-20 Fighter Emerges​

Posted on May 25, 2011 by alert5
There is a rumor on Chinese military forums that the single Tu-204-120CE operated by Air China Cargo has been transferred to the PLAAF and will get tail number 769. The aircraft was stored at Tainjin airport for a few years.

Air China Cargo Tu-204C transferred to PLAAF? - Alert 5

There is a rumor on Chinese military forums that the single Tu-204-120CE operated by Air China Cargo has been transferred to the PLAAF and will get tail number 769. The aircraft was stored at Tainjin airport for a few years. Related posts (Automatically Generated): Japan to deploy more fighters...

alert5.com

Tu-214LMK flying laboratory aircraft (registration number 64507) for Tu-160 supersonic bomber and apparently in future for Su-57 Felon also

On December 28, 2018, the Tu-214LMK flying laboratory aircraft (registration number 64507) made its first flight after conversion in Kazan. It was converted at the Kazan Aviation Plant (KAZ) named after S.P. Gorbunov, a branch of PJSC Tupolev, from a Tu-214 passenger aircraft (factory number 42305007, serial number 507, registration number RA-64507) built in 2003. The aircraft was converted into a flying laboratory of the LMK-214 multifunctional flight modeling complex of PJSC Tupolev for testing the new radar system of the modernized Tu-160M2 strategic bomber (and in the future - PAK DA), and is therefore equipped with a corresponding nose cone. The Tu-214LMK flying laboratory aircraft of the LMK-214 multifunctional flight modeling complex (factory number 42305007, serial number 507, registration number 64507) belonging to PJSC Tupolev during its first flight after completion of its conversion at the Kazan Aviation Plant (KAZ) named after S.P. Gorbunov, a branch of PJSC Tupolev. Kazan, 12/28/2018 (c) Dmitry Romashko / russianplanes.net
This aircraft was built at KAZ (KAPO) and, being owned by Financial Leasing Company (FLC), was operated in 2004-2008 under financial lease by Dalavia - Far Eastern Airlines (Khabarovsk), which went bankrupt. In 2009-2010, it was operated for some time by Aerostars (Domodedovo). After Aerostars went bankrupt, the aircraft's operation was suspended, and since December 2010, this aircraft has been in storage at KAZ. In June 2014, it was purchased by PJSC Tupolev from FLC, which also went bankrupt, for the purpose of converting the LMK-214 multifunctional flight modeling complex into a Tu-214LMK flying laboratory as part of the Tu-160M2 program. Actual conversion work began at KAZ in 2015.

Let us recall that in early 2014, the documentation of PJSC Tupolev regarding the procurement of "Reconstruction and technical re-equipment of the test base (multifunctional flight modeling complex LMK-214), OAO Tupolev of the city of Kazan, Republic of Tatarstan" was published on the state procurement portal, implemented within the framework of the Federal Target Program for the Development of Enterprises of the Defense Industrial Complex in 2011-2020. Completion of the work was scheduled for the end of 2017. The purchase cost is 1.70925 billion rubles, including 600 million rubles allocated for the purchase of a used Tu-214 aircraft of a standard design, the technical condition of which will ensure a remaining flight time of 3,000 flight hours or 600 landings (the remaining operating life of the RA-64507 aircraft is 3,353 hours or 2,213 landings).

According to the official commentary of PAO Tupolev on this project, "the goal of the work on the Tu-214LMK is to create a flying laboratory for testing in flight the onboard equipment complexes of the Tu-160 and, in the future, the PAK DA.
Source: Начаты летные испытания летающей лаборатории Ту-214ЛМК

In the Footsteps of "Buratino": How the Strategic Tu-160 Was "Crossed" with the Passenger Tu-214 in Kazan​

The fragments of the Tu-214 serial passenger aircraft program, once promoted by the Tatarstan government but pushed to the sidelines, continue to work for the benefit of the aviation industry. The Kazan aircraft plant is preparing an unusual aircraft for the first flight - an airliner of the once bankrupt airline Dalavia with the nose of a Tu-160. Why is this necessary and what does the strange decisions of Dmitry Medvedev's government have to do with it, a correspondent of BUSINESS Online found out.

CHEAP AND CHEERFUL?​

By the end of the year, the Kazan Aviation Plant named after Gorbunov, a branch of PAO Tupolev (KAZ), will take the Tu-214 with the nose of the Tu-160 to its first flight, sources in the aviation industry told BUSINESS Online. What a miracle! We asked Tupolev and KAZ to comment on this information, but received no response.

Some wits might say that the production responded to the "order" of Russian President Vladimir Putin , given during his visit to the Kazan aircraft plant and inspection of the Tu-160: the head of state then said that it was possible to think about passenger supersonic aircraft. The bacchanalia that arose in the media then and has not died down to this day, with statements about redesigning bombers for sheikhs, the already ongoing design of a business supersonic aircraft with variable-sweep wings, and so on, of course, has nothing to do with reality. However, all this also has nothing to do with the program in question. It is purely utilitarian and, in all likelihood, solves two problems: to work out elements of the Tu-160M2 program and to create a simulator aircraft for future "strategist" pilots.

Apparently, we are dealing with a program, information about which appeared on procurement portals in early 2014 — “Reconstruction and technical re-equipment of the test base (multifunctional flight modeling complex LMK-214), JSC Tupolev of the city of Kazan, Republic of Tatarstan” (within the framework of the Federal Target Program for the development of enterprises of the military-industrial complex in 2011-2020). The cost was also indicated (as far as can be judged, for one stage) — 1 billion 709 million 250 thousand rubles. The work was supposed to be completed at the end of 2017. Among other things, a used Tu-214 of a standard design was to be purchased for 600 million, the technical condition of which would ensure a flight time of 3 thousand flight hours or 600 landings. Presumably, this aircraft was a Tupolev 64507, built in 2003, which once flew for Dalavia and, after its bankruptcy in 2008, for Aerostars (it lost its operator certificate in 2011).

"Used Tu-214s can be used to train pilots - they have not yet flown their service life. Besides, civil aviation with its strict certification requirements is one thing, and military aviation, where there are none, is another," Roman Gusarov, editor-in-chief of the Aviarunet portal, noted in an interview with BUSINESS Online . "I assume that this will be something like a simulator. Not to learn how to fly a Tu-160 (after all, these machines have different flight dynamics, it's like learning to drive a bus in a passenger car), but to get used to the cockpit, control system, procedures. It is even quite possible that this is a replacement for a ground simulator, which could be comparable in price to a real passenger plane. And then, the data that needs to be entered into the simulator's brain is closed, and it needs to be transferred to some developer company. Will it leak? And Western component suppliers need to be attracted. Plus, a simulator is usually developed with the understanding that it will be replicated in dozens, but here, most likely, one is needed, or at most several. In short, the price would be astronomical. But at the same time, the simulator is closer to a real aircraft than such a "flying desk", since it can simulate the dynamics of a specific type of flight - whatever program you input, it will give you. And in this case, apparently, they decided to do it cheap and cheerful."

FROM "FLYING DESKS" TO VIP LOUNGES​

This had already happened in the Soviet Union. In the late 1970s, when the country was developing the long-range Tu-22M3 and strategic Tu-160 programs, the question arose: how to train their crews in practice? Therefore, the Tupolev Design Bureau developed a training aircraft with some of the aerobatic properties inherent in combat aircraft. The mass-produced passenger Tu-134B was taken as a basis - it more than others conventionally corresponded to the behavior of heavy combat aircraft in the air, plus by that time the military had already used the 134th to train navigators (Tu-134Sh).

The Tu-134UBL (training and combat for pilots - this is the name the aircraft received) had in common with the supersonic "Tuskas" radio communication and navigation systems, part of the cockpit instrumentation and a new... nose - similar to the Tu-22M3 and Tu-160. This was required to create an authentic view from the cockpit for the cadets. Because of this, the aircraft became 4.6 meters longer. But the Tu-134 retained its main characteristics: cruising speed - 890 km / h, range - 2300 km, ceiling - 11,800 meters.

In 1981–1984, the Kharkov aircraft plant produced 90 Tu-134UBLs. The program had two objectives: the first was to train pilots; the second was to test various systems, such as radar stations for the Tu-95MS and Tu-22M3. It should be noted that not a single Tu-134UBL was lost in a crash, which is not quite typical for a “flying desk” — it was not for nothing that the aircraft was loved by military pilots, and therefore the mocking nickname for the aircraft, “Buratino,” which was first given to the masses, did not catch on.

In the late 90s, with the onset of hard times, the Tu-134UBL began to be decommissioned (about 20 UBLs appeared in open lists of released military real estate) and converted into passenger aircraft, including VIP versions. And what? The big-nosed Tu-134 looks downright dandyishly impressive. For example, the Tu-134UBL in pseudo-Aeroflot paint and with its own name "Count Muravyov-Amursky" is used to fly the Presidential Plenipotentiary Envoy to the Far East (among others, Kamil Iskhakov flew on it ). It was transferred to transport senior civilian officials of the 11th Army of the Air Force and Air Defense. The Air Force also began to use the machine for official flights of personnel.

The next blow to UBL was the crash of a passenger Tu-134 in Petrozavodsk on June 20, 2011. At that time, Russian President Dmitry Medvedev ordered preparations to decommission the Tu-134 by 2012. Following the cessation of civil airliners, military modifications were also stopped, “with the exception of flights related to combat training.” But, as Izvestia wrote , despite this reservation, in 2012 the disgraced “Tushkas” hardly flew, the program for training and advanced training of navigators and flight personnel of long-range aviation stalled. Therefore, a year later, the military proposed to return the Tu-134 to service for training pilots and navigators, which was done. However, there are still few of these machines left, today there are hardly even fifteen of them.

Around the same time, the then Minister of Defense, Anatoly Serdyukov, ordered the preparation of tactical and technical specifications for the aircraft to replace the Tu-134UBL - it was supposed to be either the Tu-204 or Tu-214. As is now clear, the choice was made on the latter.

TENDERNESS TO THE ROARING BEAST​

Let us add that the appearance of information about the start of the LMK-214 program immediately followed the statements of the military that 30 Tu-22M3 would undergo deep modernization, and preceded the news that Kazan would resume production of the Tu-160. Let us recall that the Tu-160 assembled from Soviet stockpiles was rolled out in January of this year, and at the same time, in the presence of Vladimir Putin, a contract was signed for 10 new "White Swans". And we could see the rollout of the Tu-22M3M in August of this year.

It should be noted that the high significance of the work on LMK-214 was noted. In December 2017, the program director - chief designer of the complex Valery Benderov was awarded the title of "Honored Designer of the Russian Federation" by decree of the President of the Russian Federation. The official statement said that earlier, Valery Vladimirovich, as vice president of Tupolev, supervised the work on the rearmament of long-range and strategic aviation with new high-precision weapons, on the modernization of long-range aviation systems.

According to Andrey Frolov , editor-in-chief of the magazine “Eksport Vooruzheniy” , we are dealing with a dual-use aircraft. “Firstly, we can assume that the aircraft will be used to train pilots,” he told “BUSINESS Online”. “Considering the known data on the number of Tu-22M3M and Tu-160M2, there will be only a few training aircraft, which would logically be made from used Tu-214 and Tu-204 – there are many of these aircraft on the market… Secondly, it is possible that the aircraft is also intended for testing equipment. In this case, it is also logical that the nose is being changed: as we remember, almost all Soviet flying laboratories, on which, for example, radars were tested, were ‘long-nosed’.”

An interesting point: on August 16, during the rollout of the Tu-22M3M, a Tu-134UBL was parked on the outskirts of the KAZ airfield. Of course, one could assume that it was the aircraft of the Aerospace Forces leadership that had arrived for the celebration, but, in all likelihood, it had already been at the plant for some time: the most recent satellite images on Google Maps show that five L-39s were parked nearby, which had arrived in Kazan for the “I Choose the Sky” celebration on August 10. Perhaps the Tu-134UBL was brought in as a sample. “A full-scale stand so that assemblers could understand how our ancestors did it,” Frolov suggested.

Ikar Airlines pilot Alexander Smirnov flew the Tu-134UBL in 1992–1998, first as a cadet at the Tambov Higher Military Aviation School of Pilots (TVVAUL), then as a co-pilot and instructor at the Ryazan Long-Range Aviation Flight Crew Training Center. Incidentally, it was the Tambov School's Tu-134UBL that "played the role" of the Tu-22 bomber in the famous film "Tenderness for the Roaring Beast," which was filmed, by the way, in 1982, when the UBLs were just starting to be produced — incredible for the level of secrecy at the time.

“We trained to be Tu-22M3 pilots and started flying L-29s, and the Tu-134UBL was a transitional type, a graduation aircraft,” Smirnov told BUSINESS Online. “Yes, visually the nose was similar to the Tu-22M3, and I think it’s all about imitation, because the Tu-134UBL weighs different from the missile carrier, and has different speeds, and different cockpit instruments. What’s convenient with such a nose is that you can always see its surface, which means it’s easier to navigate during takeoff… We had at least 30 aircraft. Imagine a classic military airfield and a UBL parking lot almost the entire length of the runway. In the good Soviet years, instructors flew 600 hours a year, which is comparable to civil aviation, but after 1991 the flight time dropped. But I was still very glad that I got to the training center: back then, the Tu-22M3 hardly flew (my classmates said that they only made four circles a year), and we flew 70-80 hours, which was considered progress... It was a great machine. I don't know a pilot who would say anything bad about it. It's a pity that most of the UBLs are gone. But apparently, history is still developing in a spiral - now there will be a Tu-214."

P.S. Today, the press service of PAO Tupolev explained the purpose of creating the new aircraft in a letter to BUSINESS Online: "The Tu-134UBL is primarily intended for training cadets to fly the Tu-22M3 and Tu-160, and the Tu-214LMK is an integral part of the testing system for experimental equipment installed on modernized and newly developed aircraft. The purpose of the work on the Tu-214LMK is to create a flying laboratory for testing in flight the onboard equipment systems of the Tu-160 and, in the future, the PAK DA."

https://www.business-gazeta.ru/article/400185

(Translated from Russian to English with Google Translate)

 

[Asterion Moloc]

• Boeing 757-200 Excalibur FTA for GCAP

G-FTAI, the Boeing 757-based Excalibur testbed, taking off from MoD Boscombe Down. (Image credit: Leonardo)

https://twitter.com/x/status/1866222245275947237

https://twitter.com/x/status/1863980176859652351

https://www.facebook.com/sharer.php?u=https://theaviationist.com/2024/12/10/gcap-testbed-excalibur-first-modification/

After recent flights showing off new fuselage-mounted sensor housings, Leonardo has announced that the first modification and flight testing phase for the GCAP testbed aircraft, named Excalibur, is now complete.​

The Boeing 757 ‘Excalibur’ testbed, converted from passenger use, will be used to develop technologies for the UK Future Combat Air System (FCAS) program, of which the Global Combat Air Programme (GCAP) fighter is a major part. Flight testing has successfully certified the new fuselage mounted pods, visible on the belly and side of the aircraft, as fit for flight, and they can now be used to house sensors, electronic warfare technology, and communications hardware for development purposes.

Subsequent phases of modifications will see Excalibur equipped with a mock-up nose cone designed to simulate the proposed design of the GCAP fighter, allowing the jet to facilitate radar trials for the upcoming aircraft. This will resemble other similar testbed aircraft like the similarly Boeing 757 based ‘Catfish’. Additional fairings could be fitted to the ‘cheeks’ of the aircraft, either side of the cockpit, and pods attached to the wings.

Excalibur​

Owned and operated by UK based aviation services provider 2Excel, the airframe is based at the UK’s famous Boscombe Down facility, home to various military aviation trials units as well as the Empire Test Pilots’ School (ETPS). Before acquiring its new role and registration, the airframe was owned by charter airline Titan Airways as G-POWH. G-POWH spent several periods under lease to Jet2, and also operated some of Titan Airways’ in-house football team charters. Prior to this the airframe had a storied history, serving with Atlasjet, Ethiopian Airlines, Eritrean Airlines, Iberia, and Saudi Arabian Airlines. It arrived at Boscombe Down in 2023.

A second Boeing 757, G-BYAW, was acquired by 2Excel and completely disassembled so a hyper-accurate digital twin could be constructed with the same mass and structure as the real thing.

Excalibur is currently a UK owned and operated capability, but the work contributed towards GCAP will equally be of assistance to the other partners in the program. In the longer term, the aircraft will likely become a collaborative project as GCAP progresses further and inches closer to its final design.

The GCAP fighter, a merger of the British-Italian Tempest and Japanese F-X programs, is projected to enter service in the mid 2030s. A demonstrator aircraft will, under the current schedule, take to the air towards the end of this decade. As a sixth-generation fighter, the GCAP platform will incorporate advanced networking allowing seamless cooperation with unmanned ‘loyal wingman’ UCAVs and other manned systems, as well as advanced integrated sensors, adaptable weapon control systems, and open architecture based software allowing for simpler upgrade processes.

Aviation enthusiasts were eager to spot the Excalibur 757 as it made recent test flights with the new housings. The most extensive flight was on Dec. 3, 2024, travelling as far southwest as Cornwall and operating in an interesting pattern off the coast of Portland, Dorset.

ADS-B transponder track for the Excalibur airframe, G-FTAI, on Dec. 3, 2024. (Image credit: Flightradar24)

A Strong Pedigree​

Excalibur is far from the UK’s first foray into the realm of testbed aircraft for future fighter platforms. While many have not attracted the same attention as the Catfish or the Lockheed Martin CATbird have in the United States, they have been equally as important to the development of many aircraft systems.

ZE433, a BAC 1-11, flew as a radar and avionics testbed platform from Boscombe Down from the 1980s until the late 2000s. First being used to trial the Blue Vixen radar that would equip the Sea Harrier FA2, the aircraft was later fitted with the CAPTOR radar destined for the Eurofighter Typhoon.

• BAC 1-11 ZE433 fitted with a nose cone similar to that of a Typhoon for CAPTOR radar trials. (Image credit: fsll2, CC BY-NC 2.0)

The 1-11 saw heavy use in the UK for aircraft development purposes, with no fewer than five of the airframes having been listed on the UK military aircraft register. XX105 tested early autoland and digital cockpit technology, while XX919 was used to develop satellite communications capabilities. ZE433’s ‘sister’, ZE432, served with ETPS, while ZH763 became a flying laboratory for a variety of experiments. One notable test saw the aircraft remote controlled in the air from an accompanying Tornado, a test that shows clear lineage to present day trials of UCAVs and loyal wingmen.

Alongside ZE433, the Royal Navy additionally flew a modified HS125 business jet with a Blue Vixen radar nose for a certain time. This aircraft also had the capability to carry instrumentation devices on wing mounted hardpoints.





Most recently, in 2023 the UK defence research company Qinetiq demonstrated a radar and sensor testbed capability on G-ETPL, an Avro RJ100 quadjet, featuring the distinctive fighter-style radome on the nose. The radome appears to resemble that of a Typhoon, and will likely be involved in developing technologies for that platform, while Excalibur focuses on GCAP.

• Avro RJ100 G-ETPL of Qinetiq with the fighter style testbed nose cone. (Image credit: Qinetiq)

Historically, the nose cone treatment has even been applied to British military helicopters. Royal Navy Sea Kings were used to test the Westland Lynx’s SeaSpray radar, as well as the AgustaWestland Merlin’s Blue Kestrel radar.

While much of the testing previously accomplished with these makeshift adaptations can now be completed virtually, without modifying an existing aircraft, fortunately for those of us who follow them with interest it appears that testbed aircraft will still have a long future to come.

GCAP Testbed Boeing 757 ‘Excalibur’ Completes First Modification Phase

After recent flights showing off new fuselage-mounted sensor housings, Leonardo has announced that the first modification and flight testing phase for the

theaviationist.com

 

[Asterion Moloc]

• South Korean Boeing 737 for AESA FTB of KF-21 by @AbRaj

Apparently modified by South Africa, see the below post for more detailed info:

South Korea’s 4.5-generation aircraft has a new action. The KF21 nose is installed on a Boeing 737. Why is it modified in South Africa? _Test_Proceed_Avionics System​

2021-12-06 04:08:05 Published in International by the Screaming Stuka18

South Korea’s 4.5-generation machine KF-21 seems to have fallen silent for some time after the noise when the first prototype went offline. Many people say that it has been dismantled like a Japanese "Mind", and even the project may be discontinued. . But in fact, disassembling the first prototype on the ground is the only way for countries with weak aviation foundations to develop new types of fighters. It does not mean that it ends here and will eventually have to be reassembled. In fact, the development of South Korea's KF-21 is still proceeding step by step, and even new moves have been made recently.
The development of KF21 is still proceeding step by step


View attachment 22407
Yes, this Boeing 737 is the latest effort of South Korea’s KF-21. In fact, it has been unveiled as early as the first ten days of November, and the KF-21 airborne active phased array radar has recently been installed in preparation for avionics system testing. Having said that, everyone understands that it is the integrated avionics flight test platform (FTB) of South Korea’s KF-21. It is the same as the international practice. It is modified on a passenger or transport aircraft. It can be used for four takeoffs. Up to 5 hours of testing, more space, longer battery life, and faster test progress.
Boeing 737 before changing the KF21 nose

However, it is interesting that the place where this Boeing 737 appeared is not South Korea, but South Africa, which is thousands of miles away. This can be seen from the topography of the airport, where is such a place like Pingchuan in South Korea? And this is why the KF-21 integrated avionics flight test platform is making its first flight in South Africa. After all, the airspace in Northeast Asia is narrow and the routes are busy. As soon as this Boeing 737 starts up, maybe the entire Seoul Seoul) will be suspended.
KF-21 Integrated Avionics Flight Test Platform

Inside the cabin of this Boeing 737

Display and control terminal of KF21 test platform

On the other hand, the reason is that South Korea's KF-21 has some cooperation with South Africa in terms of electronic systems, and the modification project also requires technical support from South Africa. Although the airborne radar is owned by the domestic LIG Nex1 company, foreign aid is indispensable in other aspects. This is the current reality in South Korea. For example, it is planned to fly the KF-21 Block2 for the first time from 2026 to 2028, and even the buried bomb bay developed by the United Kingdom will be used. However, because South Korea can't handle this system, many sensors will continue to be exposed until KF-21 Block3 can completely solve the problem of the domestically-made embedded bomb bay and reach the level of "Falcon Eagle".
South Korea still can't handle it by itself
View attachment 22408

The airborne radar is from South Korea’s LIG Nex1

According to the current progress, this KF-21 integrated avionics flight test platform should have achieved its first flight in South Africa. Of course, it will return to Korea for testing in the future. Prior to this, South Korea had already modified a C-130H transport aircraft locally to test the airborne active phased array radar of the Korea National Defense Science Institute and LIG Nex1, and it had also tested the radar beam stabilization function, and measured Ground clutter interference, and conducted air-to-air/air-to-ground model tests.
Previously, South Korea changed a C130H

This way of playing is too amateur

This C130H also tested a lot of things

It's considered to be a native method

However, this method of stuffing the radar with a mobile trolley into the belly of a military transport aircraft, opening the stern door during flight, and pushing the radar out is really unprofessional. That's why this Boeing 737 was born. In fact, when the US F22, F35, Russian Su 57, and my country’s F-20 were developed, there were one or two similar aerial test platforms for avionics. These are key equipment as important as wind tunnels. With the help of South Africa, South Korea It is a preliminary climb to this technology tree. But the problem is that after so many years of reverse elimination, South Africa's own level is no longer good.
F35 radar electronic test platform

F22's avionics test flight platform

According to South Korea, ground testing of the KF-21 No. 1 prototype should begin later this year, and the first flight will be in July 2022. Now that the distance is very close, in the next time, what kind of news it will explode, let's wait and see.
I really don’t understand this picture, so let’s give it to everyone as it is

韩国4.5代机又有新动作，KF21机头装在波音737上，为何在南非改装？_测试_进行_航电系统 - 全网搜

韩国4.5代机KF-21在经过首架原型机下线时的喧闹之后，近一段时间似乎又沉寂下来了，很多人说它已经像日本“心神”一样被拆了，甚至项目都可能下马了。但实际上，将首架原型机进行地面分解，是一些航空基础薄弱的国家在研制新型战机时的必经之路，并不意味着到此为止，终归还要重新组装起来的。实际上，韩国KF-21的研制仍在按部就班地进行，甚至在最近还搞出了新动作。 KF21的研制工作仍在按部就班地进行 没错，这架波音737就是韩国KF

sunnews.cc

• Airbus A-320 ATRA (of Germany's DLR) FTB for testing AESA-Mk1 radar for German “Quadriga” Eurofighters and Spanish “Halcón I” Eurofighters

Prior to its first flight the modified A320 ATRA performed&nbsp;High Speed Taxi tests


What's flying up there? Unusual flying objects have always caused a stir. And that has probably also been the case in Braunschweig, Germany, on January 21, 2025. That was when attentive observers were able to see a very special aircraft in action for the first time over the airfield of the German Aerospace Center (DLR): the DLR’s modified A320 ATRA, which just completed its first flight. ATRA stands for “Advanced Technology Research Aircraft”.

What makes this research aircraft so extraordinary is its “nose”, which is not the one you see on a regular Airbus A320 commercial aircraft. The A320 ATRA is equipped with the nose of a Eurofighter jet that Airbus engineers from Manching developed and assembled specifically for the test aircraft.


Flying “test bed” for new Eurofighter radar

But why does the A320 ATRA need a new nose at all, and why one from a fighter jet? “We are operating the aircraft in close collaboration with the DLR and the German Armed Forces to test a new radar for the Eurofighter and bring it to maturity,” explains Airbus E-Scan radar project manager Thomas Hirsch. And for this, the test aircraft needs to have a corresponding front section to house the so-called AESA-MK1 radar (Active Electronically Scanned Array).

To ensure that the A320 ATRA can accommodate its new nose without any problems and fly safely with it, engineers and mechanics from Airbus Defence and Space and Commercial Aircraft have designed a complete new front section and reinforced the A320 airframe. All modifications were carried out in accordance with the proper procedures of the type-certification holder, Airbus Commercial Aircraft in Toulouse. In addition to integrating the new nose, the teams will, in a next step, also install extensive test equipment in the A320 ATRA cabin, including a customised Eurofighter avionic test rig and supporting cooling and power infrastructure requirements.

Longer test time under real conditions

Now that the first flight has been successfully completed, testing can begin this year. But why isn't the new radar being tested directly on a Eurofighter? “The A320 ATRA has a significantly shorter clearance process and can stay in the air longer than a Eurofighter,” says E-Scan radar project manager Hirsch. This means that the “testing time” in a real-life environment, i.e. in the air, is considerably earlier, quicker and with a longer duration on an A320. These aspects significantly speed up the radar development process.

Upon completion of the development, the AESA-MK1 radar is then to be integrated and used in the latest generation of Spanish “Halcón I” and German “Quadriga” Eurofighters - and make the fighter jet even better than it already is. The radar will improve the Eurofighter's capabilities in air-to-air and air-to-ground operations and also equip it with electronic warfare functions.

A unique test aircraft: the A320 with the Eurofighter nose takes off for the first time

Airbus engineers are using a modified A320 aircraft to test and mature a new radar for Eurofighter combat jets.

www.airbus.com

Could not find similar aircrafts for Rafale or Gripen yet, may be language issue in search algos??

 

[Asterion Moloc]

• Northrop Grumman’s Bombardier CRJ Testbed Aircraft fleet of 3 aircraft​

AN/APG-83 Scalable Agile Beam Radar (SABR) seen installed on one of the CRJ testbeds as well as LITENING targeting pod on its ventral hardpoint. In the background you can see one of the old BAC One-Eleven testbeds that the CRJs largely replaced. The image was taken at the company’s facility at Baltimore/Washington International Airport, Northrop Grumman


One of the company’s CRJ testbeds fitted with the seeker for the anti-access/area denial (A2/AD) missile that is part of the Stand-in Attack Weapon (SiAW) program., Northrop Grumman

The NG testbed, previously fitted with fighter aircraft nose radomes, was photographed showing what appears to be a forward section of the new AIM-260 Joint Advanced Tactical Missile.​

Captured by aviation photographer Colin Clark at Nellis Air Force Base, Nevada the images show the CRJ700 aircraft outfitted with a missile nose where it has previously, and recently, carried an F-35 radome. The aircraft, N806X, is registered to Northrop Grumman Systems Corp, and is one of three CRJ700s in their service.

The nose bears a striking resemblance to previous renderings of the AIM-260 Joint Advanced Tactical Missile (JATM). If confirmed, this would be the first public sighting of the new air-to-air missile, or at least part of it.

https://twitter.com/x/status/1920271661795852561

Northrop Grumman CRJ700 Testbed Seen Sporting New Missile Nose

The NG testbed, previously fitted with fighter aircraft nose radomes, was photographed showing what appears to be a forward section of the new AIM-260

theaviationist.com

This Gonzo-Looking Regional Jet Just Put The F-16's New Radar To The Test

Northrop Grumman's pair of reconfigurable CRJ testbed aircraft have been extremely busy as of late, including flying in major air combat exercises.

www.twz.com

A Modernized Flying Testbed Force​

Northrop Grumman has long leveraged testbed aircraft for a huge range of research and development initiatives dating back to the company’s founding. In more recent times, platforms ranging from BAC One-Elevens to Sabreliners to Gulfstreams have been heavily modified to act as surrogates for various airborne sensor, electronic warfare, mission, and communications systems. So, the company is clearly a true believer in the benefits of testbed aircraft. This has manifested itself in its push to modernize and consolidate, at least to some degree, its testbed platforms via the acquisition of a small fleet of CRJ-700s, which has now grown to three airframes.

These are nearly identical aircraft, which often get viral attention on social media due to their ability to transform into many different configurations, some of which look quite bizarre. They are based out of Baltimore/Washington International Airport, Maryland, and support roughly 50 programs a year. Flying testbeds fleets are usually made up of a hodgepodge of older airframes that are cheap enough to deeply modify for various uses, just as Northrop Grumman’s fleet had been prior to the arrival of the CRJs. Now having such a modern fleet of test jets that is purpose-engineered for modularity is something somewhat unique to the company.

https://twitter.com/x/status/1436104091537600525

And when we say modular, we mean modular. The CRJ testbeds’ cabins, which would normally seat roughly 75 passengers, have been reconfigured with control stations, 10 laboratory racks, and a chiller to cool mission systems and other electronics. Additional power-generation capabilities were also added.

Externally, these fascinating airframes can be equipped with entirely different noses to accommodate radars, missile seekers, and large electro-optical systems. They also have a ventral hardpoint capable of carrying a variety of pods, such as the AN/ASQ-236 Dragon’s Eye radar, the LITENING advanced targeting pod, or a large canoe fairing that can be loaded with systems.

Another dorsal attachment point atop the aircraft can house other sensors or communications systems. There are even provisions for side arrays to be installed on either side of the fuselage.

In addition, Northrop Grumman’s CRJ test jets are not only capable of testing the hardware bolted onto them, but also the operational software that underpins that hardware, and in highly dynamic environments. These include large force employment (LFE) exercises where they would be pitted against a physical enemy force and fly alongside a friendly one. In fact, they could masquerade as a fighter jet in a formation of others — the same types that the systems they are testing are slated to end up on. So we are talking about a flying transformer of sorts here that was purposefully engineered for maximum adaptability while leveraging one of the hardest-working and most reliable airliner airframes on the planet. Once again, they are remarkably unique as a testing force — no other prime defense contractor has a fleet quite like it.

Digital Shadow Will Insert Northrop Grumman's CRJ Testbed Aircraft Into The Virtual Realm

The highly adaptable CRJ-700 testbed jets are getting a 'digital twin' to allow them to virtually flight test hardware before ever taking to the sky.

www.twz.com

• Raytheons's Boeing 727 based Raytheon Multi-program Testbed (RMT)

Radar-Toting 727 Testbed “Voodoo 1” Appears Over Saipan​

Raytheon's one-off 727 testbed jet has ventured very far from home to test its sensor payload as part of a major exercise in the Pacific.


The War Zone asked the head of the F-15 radar program for Raytheon, Michelle Styczynski, about Voodoo 1 and how it plays into the company’s developmental initiatives. Here is that exchange:

Tyler: What is the APG-82’s lineage in relation to other Raytheon products, including outside of the F-15? Where does that lineage come from? And one oddball part of this—how did ‘VOODOO1,’ your 727 testbed jet, play a role in developing this new radar?

MS: Yeah, what a great question. So what Raytheon is really good at is obviously trying to provide cost-reduction alternatives for customers. What you’re getting from the APG-82 is actually born from the APG-79 radar that’s on the F-18 and also the legacy APG-63V3 that sits in the F-15C/D aircraft. Essentially, both of those radars came together to create the APG-82. We leveraged all of those different developments in order to get this latest APG-82V1 radar.

With regards to the [727] aircraft, that’s our RMT [Raytheon Multi-program Testbed] platform. That airplane has definitely given us a leg up in terms of testing out the different developments that we do. We use that aircraft to essentially take what we do in our lab and put it into the sky before it gets into a fighter test jet. We can test certain things and work out any bugs that we may see, so it helps with cycle time as far as development is concerned, and we also try to cut costs for our customers by doing so. We have definitely done this on our domestic developments and are doing this on our international developments… It is a really big part of how we cut down development cycle time to get the customer faster technology quicker.

Tyler: Is there an F-15 cockpit in there? How does the 727 act like an F-15?

MS: Yeah, there are different simulators. I don’t have the specifics with regards to that, but I do know that we do have different simulators that… What’s the word? Well, that simulate… I keep using the word simulator over and over again but it simulates the ADCP II (Advanced Display Processor II) from Boeing, there are simulations on a nav that we would get… and so it’s just a giant flying simulator in my mind. But I’m probably not doing it as much justice as I could because that thing has been providing us a significant amount of lift across multiple programs to get things done.

Teams are actually looking at capacity across the Raytheon technology portfolio to continue to exploit the legs up that we do get in our development to expand that further in terms of investing for more aircraft… Because that airplane in itself right now has very little capacity with all the work that it’s doing… So it’s definitely being put to use by our customers.

Raytheon’s Boeing 727 testbed also has a detachable ventral gondola-type fairing under the forward fuselage that could accommodate various kinds of sensors, such as radars with synthetic aperture imaging functionality and multi-spectral cameras, and other subsystems. Pictures from plane spotters in Japan, as well as those in the United States that caught the aircraft flying near Salt Lake City and around southern California earlier this year, show the gondola configuration. The Japan images suggest the presence of a low-observable AESA radar or some other type of conformal sensor in a rhombus aperture on the right side of the pod. Larger array, or at least a discolored panel, is on the opposite site.



The training on Saipan is more involved and includes the use of four 55-foot-long simulated enemy road-mobile ballistic missile launchers, pictures of which are seen below, among other things. Unsurprisingly, the mock ballistic missiles have a general look that is vaguely similar visually to various Chinese types, such as the DF-21 and DF-26, which are of particular concern to U.S. military planners. Detecting and being able to enact a kill chain to destroy these types of missiles would be key during an actual conflict with China or another state with robust ballistic missile capabilities.

The orbit that N289MT was tracked flying around Saipan and Tinian could align with a test of one or more sensor systems, with the mock ballistic missiles potentially being among the targets of interest. The experiments that the aircraft is supporting could involve new or improved communications and data-sharing suites, as well. The U.S. military, as a whole, is only increasingly interested in ways to gather a wide array of information, fuse it together and otherwise process it, and then disseminate it to where it can do the most good, and do so as quickly as possible. Testing of advanced networking capabilities is an ever-more central part of major U.S. military exercises across the board.

Beyond that, conducting whatever these experiments might be in association with Valiant Shield 22 can only offer a valuable opportunity to see how whatever systems are on board Voodoo 1 perform in large force scenarios. This exercise in particular is taking place in a real-world environment that is exactly where a further high-end conflict might occur, too.

More details about Voodoo 1’s flight from Guam, or at least hints as to exactly what the aircraft may have been doing, may well come as Valiant Shield 22 proceeds or in official news about the exercise after it wraps up.

Radar-Toting 727 Testbed "Voodoo 1" Appears Over Saipan

Raytheon's one-off 727 testbed jet has ventured very far from home to test its sensor payload as part of a major exercise in the Pacific.

www.twz.com

What we need is some thing like these modular test aircrafts to be made available for Data Pattern or AMPL to test their radars which they are saying can be used Su-30 etc(Data Pattern esp) as they mentioned in Aero India.

Alternative to BARS radar on Su 30MKI. Please note, here the antenna can move left to right and up as well as down, whereas the original BARS antenna is fixed.A system by Data Patterns.

View attachment 40369

https://twitter.com/x/status/1889269422503669903

View attachment 40402

AMPL website has open range testing of seeker head for a SAM/AAM

https://astramwp.com/outdoor-antenna-test-range/

what we need is something like this for end-game scenario apart from the airborne test beds as shown above

Missile Engagement Simulation Arena (MESA)​

The Howland Company led the concept design team that established performance requirements for Missile Engagement Simulation Arena (MESA) at the Naval Air Warfare Center Weapons Division at China Lake in California.

 

[Asterion Moloc]

• USAF's RAT55 Boeing 737 based Radar Airborne Testbed (RAT)​

World’s Most Secretive 737 Just Made A Very Rare Appearance​

RAT55, a highly modified Air Force NT-43A, bounces around between secretive test bases and is used to collect radar data on stealthy aircraft in-flight.
AT55, U.S. Air Force Materiel Command’s extremely shy NT-43A/737-200 converted into a grotesquely modified radar cross-section measurement platform just flew across the country for an unknown reason. During its trip, it made two stops, one in Arkansas and one in Texas, the latter offering very rare close-up views of Earth’s most fascinating 737 going about its business.

RAT55 arrived at Rick Husband International Airport in Amarillo, Texas, “at 2:40 pm and departed at 3:40 pm. It was cleared back to Tenopah Test Range Airport,” Jason Zicker, an aviation photographer who took the videos below and posted them on social media, told TWZ. Zicker said he was alerted to RAT55’s arrival by a fellow plane spotter.

https://twitter.com/x/status/1925658895487324500

https://twitter.com/x/status/1925652913570877752

“As far as I know, it was just for gas,” said Zicker, who was kind enough to let us use his video. “RAT55 did have a flight plan to come here a couple of months ago, but never showed up.”

The aircraft flew from the Nevada Test and Training Range (NTTR) to Northwest Arkansas National Airport. It stopped at Amarillo on the way back, likely for fuel. It isn’t clear why it went to Arkansas at this time. We asked Air Force Materiel Command if they could provide any information as to RAT55’s puzzling trip and they replied: “Regarding your query, I do not have any details to provide.”

It is interesting to note that King Aerospace has a presence at Northwest Arkansas National Airport. In 2022, RAT55 appeared at a different King Aerospace facility at Admore Municipal Airport in Oklahoma during another rare outing. Whether or not its latest trip is again tied to a visit to this company, which specializes in heavy maintenance and deep modification work, including for the U.S. military, is unknown at this time. TWZ has reached out to King Aerospace for more information.

https://twitter.com/x/status/1924900092454306085

The name RAT55 is actually used for the jet’s callsign, although as RATT55, with an extra “T.” On this particular outing, the jet has been using the callsign Stormy 29.

The “RAT” in the name stands for Radar Airborne Testbed, while the “55” refers to the last two digits in its tail number. RAT55 spends most of its flying life in the vast and remote range complexes that span South-Central California and Southern Nevada. The aircraft seems to live at the high-security Tonopah Test Range Airport (TTR) — famous for its shadowy aircraft programs — and spends time in the skies near Area 51 and Edwards Air Force Base. While the one-off NT-43A has ventured beyond its usual protected operational confines — it needs major servicing just like any other 737 — usually these trips seem to be planned to expose the aircraft to minimal public eyeballs. That is clearly no longer the goal.

Regardless, RAT55 is unlike any other aircraft on the planet, and it is absolutely critical to the development and sustainment of America’s aerial stealth technology. Simply put, RAT55 uses its two huge radar arrays — one front and one back — to take fine measurements of the radar signatures of stealthy aircraft while flying through the air near them. It does this to validate low-observable designs and skin treatments. It also has electro-optical/infrared capabilities above its radomes and can be fitted with dorsal fairings for other systems. While there are facilities on the ground that can take similar measurements of aircraft flying through the air, doing it from another specially-equipped aircraft in the air allows the target to be measured from every angle, including from overhead aspects, and continuously.

Even when B-2 Spirits come out of depot maintenance, they usually spend time in the sky with RAT55 to validate that the work done fits established design goals and parameters. That is the most visible of the NT-43A’s work, but the aircraft is also involved with the most advanced and secretive stealth aircraft development programs in the Pentagon’s portfolio, many of which we don’t know about and likely never will.

https://twitter.com/x/status/1321621668553322496

Considering all of the combat aviation developments now underway in a new era of so-called ‘great power competition,’ RAT55 is presumably busier than ever, and will be flooded with work soon as many programs mature into a flying state. From the B-21, to a plethora of new advanced drones, to the F-47 next-generation fighter, the stealth business is booming. At the same time, RAT55 is a very old aircraft, and dwindling support for first-generation 737s is surely becoming an issue. With this in mind, it is somewhat puzzling why it isn’t being replaced or at least augmented. Then again, it could be, and we won’t know until that new aircraft materializes somewhere.

That’s the abbreviated version of what we know about RAT55, you can read more about the aircraft and see the best images ever taken of it in this past feature of ours.

While we don’t know why RAT55 came out of the shadows for this jaunt across the U.S., it sure was a great opportunity for aviation enthusiasts to spot a truly one-of-a-kind plane, and a very clandestine one at that.

World’s Most Secretive 737 Just Made A Very Rare Appearance

The highly modified NT-43A bounces around between secretive test bases and is used to collect radar data on stealthy aircraft in-flight.

www.twz.com

The RAT55 must have been used to test the B-2's stealth coatings before the strike on Iran, the dates seem to match up now in hindsight
@Parthu @Rajput Lion @randomradio

 

[randomradio]

This one's France's testbed for Rafale's avionics.

https://twitter.com/x/status/1813171987092492322

 

[randomradio]

DRDO's Anusandhan for AMCA.

https://twitter.com/x/status/1418126132352741378

It's yet to be modified.

 

[randomradio]

Two Hawker 800 testbeds for Uttam and EODAS.

https://twitter.com/x/status/1499716343167258625