Lockheed Martin F-22 Raptor

Back to the F-22, it’s interesting that the stick sends a g command above 275 knots and pitch rate command below that airspeed. I recall a test pilot with callsign C-dip (don’t remember his name) who gave a presentation to us UCLA aerospace students at Edwards in 2016 said something similar. He also mentioned that the amount of g that flying the F-22 subjects the pilot to compared to other airplanes is not a pleasant experience.

The YF-23 had basically the same pitch schedule. According to Metz's YF-23 book, pitch command it was for AoA below cornering speed and G above that.
 
F-22 AIRST installation
F-22 AIRST -
The geometry of the roof panels of the AIRST compartment looks very much like the notches in the bulkheads as seen in a structural view of the F-22 forward fuselage in an earlier post. Perhaps an IRST system can be fitted into this bay in a later F-22 Block upgrade.

There were statements that there was a lack of “real estate” under the F-22’s nose for an EOTS, and I think that may have to do with its specific dimensions compared to proposed the AIRST configuration that we’ve seen so far; the EOTS is a “tall” sensor while AIRST is a “long” sensor. I saw this mentioned elsewhere, but a modified IR receiver hardware from IRST21 may be a better fit in that space.
 
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I've seen pictures of the second and 3rd fan stages before but this is the time I've seen the whole fan module. Despite the first stage blades being snapped off, (you can see they're hollow with reinforcement ribs) it's quite a high pressure ratio.
 
The F-22 flight control system to my knowledge is a triplex architecture and if this issue was cause after washing then this could have been an incident similar to the B-2 Guam crash where all air data probes/ports had moisture affecting all three channels or the water got into where the FCCs reside. From the investigation simulation video, it seems continued flight maneuvering may have been moving residual wash water around, but I am just speculating of course.

For a triplex or quadraplex FCAS, there is voting logic so the it seems a lot of water may have worked its way into areas which affected all three FCC channels, not a good thing if that was the case. Fly-by-wire is great but, these are the potential gotchas where good design practice comes into play in regards to hermetic sealing and liquid proofing. When I was on CVN-65, the squadron guys washed the hell out of our aircraft but they were all also hydromechanical/CAS flight controls.
 
Corruption of the air data system by blocking one or more ports has a significant history of bringing aircraft down. Not all of them FBW, there's a couple of 757s in there IIRC, but FBW aircraft are particularly vulnerable to it, because there's a coupling of the air data outputs directly into the generated commands to drive the control surfaces that the pilot doesn't necessarily see. It tends to be airspeed that's the parameter at fault and ISTR some proposals to generate a synthetic airspeed value for comparison/sanity checking- possibly as part of the MAX aftermath?

WRT the pilot having had an FCC advisory prior to takeoff, an advisory isn't necessarily a no-go, and in this case clearly wasn't. With 777 I know we were allowed one or two lanes (3 FCC channels, each of 3 lanes) to be non-functional without the aircraft failing the minimum equipment dispatch list.

"but, these are the potential gotchas where good design practice comes into play in regards to hermetic sealing and liquid proofing."

They're pressure sensors, they have to be open to the atmosphere, and it's blocking that access that is the problem. Short of moving the air data computer away from using static and dynamic pressure, you're going to keep having a sensitivity to them being blocked.
 

Mitchell Institute is advocating a much bigger push for 5th generation fighters and the upcoming NGAD. I suppose it will really come down to a cost analysis as well as airframe availability. Over the long run, I do wonder what the price of extending the F-22 is compared to the F-15EX acquisition.
 
Filmed in July 2020 at Joint Base Elmendorf-Richardson in Anchorage, AK. during a F-22 "Raptor" demonstration by pilot Maj. Joshua "Cabo" Gunderson. All footage was shot on the Phantom Flex4K at 1000FPS out of the open door of a UH-60 "Black Hawk" helicopter hovering at about 3000 feet.
View: https://www.youtube.com/watch?v=opE6u6Fj5Wo
 
Donald Rumsfeld called; he wants his title back…
I forgot about Mr. "Transformational". (Heh, he'd fit right into today's administration.) Seems like they've been having a contest to see who's the worst.
 
Donald Rumsfeld called; he wants his title back…
I forgot about Mr. "Transformational". (Heh, he'd fit right into today's administration.) Seems like they've been having a contest to see who's the worst.
Cheney allowing the massive “peace dividend” and overseeing massive strategic weapons modernization cancellations
 

$10.9 billion over 10 years, substantially more than REDI II’s 6.9 billion over 9 years. For this kind of money there better be some sweet upgrades.
 
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If you read that story you will see that some will be for logistics support as well - it wouldn't surprise me if that is a fair amount.
 
There is logistics as part of this contract, but I believe Lockheed Martin was already given a five year $7 billion maintenance contract for the F-22 in December 2019.

 
There is logistics as part of this contract, but I believe Lockheed Martin was already given a five year $7 billion maintenance contract for the F-22 in December 2019.


This is a broad IDIQ contract (where the top number may or may not be realized through to year performance period) that is focusing on developing, integrating, testing, and sustaining future F-22A capabilities across the entire enterprise. There is a BAA from last year that has a little bit more details on what they are looking for.

One would assume that this includes funding for the AIM-260 JATM integration and testing on the F-22A given that it is the first platform to receive that capability.
 
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I seem to recall there was talk about the Raptor getting substantial funding for a new classified sensor a year or so ago. Defense press at the time speculated a advanced IRST. Not sure what the status of that program is.
 
The retirement would begin sometime in the early to mid 2030s provided NGAD sticks to those timelines. It will be a while after that before all units transition to the NGAD. Its a process and will happen over several years. In his "fighter roadmap" presentation at AFA last month, Gen. Kelly was clear that they will need to be modernized to keep them relevant in the 2020s and beyond as they transition to NGAD. They are not going to turn off the tap on Raptor modernization even if they plan on retiring the fleet as soon as NGAD becomes viable.
 
Even when there are more NGADs then F22s the old Raptor may still stay around for a few years depending on how international bullshit is flowing.

The 150 F22s are a powerful force and not many have aircraft that can hold its own against it. It days is far number compare to the original plan of flying til what was it, 2050 ircc?
 
The F-22 wouldn't be replaced and retired because of its lethality aspect but because of the cost to sustain and operate a fragmented small operational force. If NGAD fields in time, and is more capable compared to the F-22A then the USAF will do it. The O&S savings can be applied to the rest of the TacAir fleet including freeing up capacity to transition some of the manpower to help stand up NGAD. Ultimately though, when the F-22's retire will be determined by how successful the AF's NGAD efforts are.
 
This is a broad IDIQ contract (where the top number may or may not be realized through to year performance period) that is focusing on developing, integrating, testing, and sustaining future F-22A capabilities across the entire enterprise. There is a BAA from last year that has a little bit more details on what they are looking for.

One would assume that this includes funding for the AIM-260 JATM integration and testing on the F-22A given that it is the first platform to receive that capability.

The pre-solicitation contract document last year didn’t really have much details on what they’re looking for, it’s pretty generic language calling for modernization kits. I also recall an interview with the F-22 program manager that sensor enhancements were being studied, with the desire for an IRST. He did say that it’s not the AAQ-40 EOTS due to space constraints (may have to do with the shape of the bay under the nose) and they’re looking at other options. Perhaps the IRST21 receiver?


The Department of the Air Force, Air Force Material Command (AFMC), Air Force Life Cycle Management Center (AFLCMC), Fighters & Advanced Aircraft Directorate (AFLCMC/WA), F-22 Program Office (AFLCMC/WAU), Wright-Patterson Air Force Base, Ohio (WPAFB) intends to acquire the lead integrator responsibilities for the following efforts on a sole source basis from Lockheed Martin Aeronautics (LMA):
- Enterprise management
- Studies, analyses, and demonstration projects
- Modernization hardware development
- Modernization hardware kit procurement
- Support to Combined Test Force & system labs
- Trainers modernization and sustainment
- Flight software modernization and sustainment
The proposed contract is a follow-on effort to the Raptor Enhancement, Development, and Integration II (REDI II) contract and will satisfy future modernization requirements, enterprise management, and select sustainment requirements to improve efficiencies within the F-22 program. It is contemplated that the ID/IQ contract will be awarded by June 2021 with a base ordering period of 5 years and a 5 year option.
 
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From Olsen v. Lockheed:

"The F-22 requires numerous different coatings to be applied to the skin of the aircraft. The initial requirements were for three layers of coating to be stacked together in the following order: The first coating is a primer designed to smooth and seal the surface of the skin and promote adhesion of the conductive coating. The second is a conductive coating consisting of silver flakes mixed with polyurethane materials and intended to conduct, dissipate, and reflect the RADAR waves away."

There are a couple of reasons the airplane's base coating is silver, including:

- Using a conductive surface below the RAM layer makes both the RAM and shaping more effective
- The F-22 OML has many different materials - composites, aluminum, titanium, etc. - all with different electrical properties. The conductive coating effectively homogenizes the electrical properties visible to radar across most of the OML and keeps radar from seeing scattering sources inside the aircraft

From "Lockheed Martin's Affordable Stealh":

"Conductive Surfaces
A common misunderstanding is that composite skins are used to make aircraft stealthy. In reality, many composites are partially transparent to radar, and expose the internal structure, wiring and components to the radar, which is the last thing a low observable designer wants. These components add up to an extremely large signature. In most Low Observable aircraft, the outer surfaces of the aircraft are coated with a metallic paint, so that the radar cannot pen- etrate into the aircraft"

Most US stealth aircrat use a highly conductive "base" layer.


What you are seeing here is the F-22 with the conductive silver layer applied, but the other layers not yet applied. All F-22s have the same silver layer but you rarely see it as it is covered by the other layers - RAM, IR coating, etc.
 
From Olsen v. Lockheed:

"The F-22 requires numerous different coatings to be applied to the skin of the aircraft. The initial requirements were for three layers of coating to be stacked together in the following order: The first coating is a primer designed to smooth and seal the surface of the skin and promote adhesion of the conductive coating. The second is a conductive coating consisting of silver flakes mixed with polyurethane materials and intended to conduct, dissipate, and reflect the RADAR waves away."

There are a couple of reasons the airplane's base coating is silver, including:

- Using a conductive surface below the RAM layer makes both the RAM and shaping more effective
- The F-22 OML has many different materials - composites, aluminum, titanium, etc. - all with different electrical properties. The conductive coating effectively homogenizes the electrical properties visible to radar across most of the OML and keeps radar from seeing scattering sources inside the aircraft

From "Lockheed Martin's Affordable Stealh":

"Conductive Surfaces
A common misunderstanding is that composite skins are used to make aircraft stealthy. In reality, many composites are partially transparent to radar, and expose the internal structure, wiring and components to the radar, which is the last thing a low observable designer wants. These components add up to an extremely large signature. In most Low Observable aircraft, the outer surfaces of the aircraft are coated with a metallic paint, so that the radar cannot pen- etrate into the aircraft"

Most US stealth aircrat use a highly conductive "base" layer.


What you are seeing here is the F-22 with the conductive silver layer applied, but the other layers not yet applied. All F-22s have the same silver layer but you rarely see it as it is covered by the other layers - RAM, IR coating, etc.
Thanks for explaining it.
 
 
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