The secretive U.S. Air Drive NT-43A RAT55 was noticed flying with a NASA callsign in one of many areas reserved for the launch of the Artemis II mission, reverse to the one utilized by the WB-57 Canberra.
NASA is about to launch the Artemis II mission on Apr. 1, 2026, at 6:24 pm EDT (22:24 GMT), which would be the first crewed lunar flight since Apollo 17 in 1972. As ordinary for NASA missions, one of many company’s WB-57 Canberra high-altitude analysis plane will observe the launch whereas flying within the airspace surrounding the Launch Complicated 39B of the Kennedy Area Heart (KSC), from the place the Area Launch System (SLS) rocket and Orion spacecraft will depart.
Tomorrow, we launch.
At sundown tonight, Artemis II waits on the pad, prepared to hold astronauts doubtlessly farther than any people have traveled in additional than half a century.
The subsequent period of exploration begins. pic.twitter.com/vdABkjRrnf
— NASA Administrator Jared Isaacman (@NASAAdmin) April 1, 2026
Nonetheless, it seems that the WB-57 will likely be joined by one other specialised, rather more secretive asset: the U.S. Air Drive’s NT-43A. The highly-modified Boeing 737-200, higher identified with its callsign RAT55, is normally employed as Radar Airborne Testbed (RAT) thought for use nearly solely to judge the radar signatures of stealthy plane.
#A10635/#AE654A as #NASA522 RATT55 on a NASA mission!
— Norb (@norb420) March 31, 2026
“Thought” might be the important thing phrase right here, as one wouldn’t count on this platform to be observing the launch of a NASA mission, since SLS and Orion should not stealth plane whose radar signature must be evaluated. Though there isn’t a official affirmation and we are able to’t make certain in regards to the involvement of RAT55, there are some hints price noting.
The primary and extra apparent is that the plane was tracked whereas flying on Mar. 31 with a NASA callsign, particularly NASA522. The identification of the plane was additionally confirmed by a photograph despatched to us by @Brevardjetphoto, which you’ll be able to see as the duvet of this text, captured because the plane was flying over Melbourne, Florida, on the way in which to its assigned space.
That is right, there are two separate NOTAMs for assist plane that match each flight tracks. This was an apparent rehearsal. pic.twitter.com/X3i5RbP4T2
— Dillon Shropshire (@Dillonshrop06) April 1, 2026
The second is that the NT-43 was flying on the identical time of the WB-57, with every occupying an space reserved by NOTAMs (NOtice To AirMen) for the launch.
Particularly, the WB-57 was flying in an space reserved to the south of Launch Complicated 39B. The WB-57’s presence was additionally talked about within the NOTAM 03/652 (KZMA-A1037/26) itself:
!CARF 03/652 ZMA AIRSPACE DCC ARTEMIS II WB-57 SUPT STNR ALT RESERVATION WI AN AREA DEFINED AS 283100N0803100W TO 280300N0792900W TO 273700N0795000W TO 280000N0810000W TO POINT OF ORIGIN FL450-FL500 2604012100-2604020100
The NT-43 was flying in an space reverse to the WB-57’s, to the north of the launch pad, reserved by NOTAM 03/643 (KZMA-A1035/26):
!CARF 03/643 ZMA AIRSPACE DCC EROP K0949 WINDOWABC SUPT STNR ALT RESERVATION WI AN AREA DEFINED AS 285000N0804700W TO 290400N0792900W TO 292800N0793400W TO 291500N0810100W TO POINT OF ORIGIN FL200-FL350 2604012125-2604020105
Each plane had been seen on flight monitoring web sites, additional confirming their loiter areas. Furthermore, AirNav Radar’s flight exercise web page for NASA522 mentions a scheduled flight for Apr. 1 at 5 pm, thus earlier than the launch (deliberate at 6:24 pm), along with the Mar. 31 flight.
The mix of all these components seems thus to level to the NT-43 RAT55 getting used to gather knowledge in regards to the launch of Artemis II in assist of NASA. The tracks additionally allowed to find out that the NT-43 is flying from MacDill Air Drive Base, Florida, whereas the WB-57 is working from the Kennedy Area Heart’s historic Shuttle Touchdown Facility (SLF).
It’s nevertheless not attainable to find out which kind of information will likely be collected by this specialised plane. As talked about earlier, this plane is normally employed to judge the radar cross part (RCS) of stealthy plane by utilizing two very giant radar arrays hosted by two radomes on the nostril and tail, which give the plane its attribute look.
The plane has additionally electro-optical/infrared (EO/IR) sensors put in on each radomes, though their capabilities are nowhere close to those of the WB-57’s giant sensor put in on the nostril. The plane may also be fitted with dorsal fairings for added tools.
Dwell from Kennedy: Artemis II launch protection is underway. We’re monitoring each milestone of right now’s historic launch! Go to our weblog for detailed updates: pic.twitter.com/bv9824UH7Q
— NASA’s Kennedy Area Heart (@NASAKennedy) April 1, 2026
For this assist position throughout rocket launches, NASA employs a fleet of three WB-57s, nevertheless just one, N926NA, is at the moment operational. As we reported in January 2026, the WB-57 N927NA suffered an emergency gear-up touchdown and it’s unclear how lengthy wouldn’t it take earlier than it returns operational.
The third plane, N928NA, is ready for the completion of a serious inspection which was placed on maintain, whereas N926NA accomplished it in February. It’s thus attainable that the NT-43A is filling in for the 2 WB-57s which can be at the moment grounded.
A Related Case
In the course of the Apollo program there was one other specialised U.S. Air Drive plane supporting NASA: the EC-135 Apollo/Vary Instrumentation Plane (A/RIA), which later grew to become the Superior Vary Instrumentation Plane (ARIA). The platform was designed to complement the land and sea based mostly monitoring stations, protecting the telemetry gaps.
This functionality was wanted each by NASA to trace their crewed spacecraft and the Air Drive to trace missile exams. Thus, NASA and the Air Drive funded this system collectively and transformed eight C-135 plane into EC-135N fashions.
Among the many modifications was a particular nostril radome on the nostril, internet hosting a 7 foot diameter P and S-band receiving dish, in addition to probe antennas on the wings, and a trailing wire HF antenna. These modifications gave the plane a extremely distinct look, with a really noticeable bulbous nostril.
In the course of the Apollo missions, ARIAs would fly the place they had been wanted, and would obtain and file the telemetry knowledge of the spacecraft on magnetic tape recorders. Along with this, they had been additionally used as a receiving and transmitting base for verbal capsule communications between Houston and the spacecraft.
Following the conclusion of the Apollo and Skylab applications in 1975, the ARIA jets was re-designated as Superior Vary Instrumentation Plane and to file telemetry throughout DoD missile exams. The plane had been additionally re-engined, leading to a re-designation to EC-135E.
In 1982 the USAF bought eight Boeing 707-320C’s from American Airways and transformed them to ARIA plane, designating these 8 as EC-18Bs. The EC-18Bs had been bigger than the EC-135Ns, and had been able to carrying further cargo, and taking off from shorter runways.
You’ll be able to learn extra in regards to the EC-135 ARIA on this story we printed right here at The Aviationist in 2020.
NT-43A RAT55
The NT-43A is contemplating one of the crucial secretive variants of the Boeing 737 collection. The plane was initially a T-43 coach, based mostly on the Boeing 737-200 airliner, later transformed to the brand new configuration and assuming the “NT” designation, the place the “N” prefix stands for “Particular Check, Everlasting.”
The plane is fitted with superior radar know-how, with two very giant radar arrays hosted in particular radomes on each the nostril and the tail. Every radome additionally has a small electro-optical/infrared (EO/IR) sensor on high, and extra tools will be put in in dorsal fairings that generally are seen on the plane.
The RAT55 callsign reportedly comes from the time period Radar Airborne Testbed (RAT) and the ultimate numbers of the NT-43’s serial 73-1155. The secretive platform operates primarily from Groom Lake, in any other case referred to as Space 51, however generally it additionally make public appearances outdoors the Nevada Check and Coaching Vary (NTTR).
RAT55 is assumed for use nearly solely to judge the radar signatures of stealthy plane. This contains new designs and prototypes in addition to present platforms just like the B-2 Spirit, which should have their stealth capabilities examined frequently to make sure the plane’s radar cross-section readings are at their anticipated ranges.
