Lockheed Martin F-22 Raptor

I have a question concerning F-22's empty weight. It is often cited by various parties to be 19.7 tons.

But looking into the past, weight was much less. There is YF-22, weighing just under 15 tons. And while It was a demonstrator, it was still probably wise to keep it close to final configuration weight. Demonstrating something for one weight and then making another plane that weighs 33% more just doesn't seem wise. X-35 demonstator weighed 12 tons, and final F-35A weighs 13.15 tons. An increase, but not that much of an increase.

And then there is this article: https://www.flightglobal.com/news/articles/f-22-weight-increase-agreed-26820/
which states F-22 (not YF-22) weighed 13,980 kg in 1992 at preliminary design review, and its weight increased to 14,365 kg in 1995, at critical design review. Usually, after a critical design review there is very little changes to the design...

While some may say that the weight did not include various radar absorbent materials, I find that implausible, as not only are they supposed to be part of the plane's structure, but also if RAM is such a huge factor in plane's weight, it would have been part of the calculation to begin with, as such huge differences cause major changes in performance.


So questions are:

How and why did F-22 get from 14,365 kg to 19,700 kg?

And when did that change happen?
 
I wonder if the empty weight for the purposes of the PDR/CDR was just for the bare fuselage (things within LM's control) so maybe not including the engines? That's around 3.6 tons right there. Just a wild-assed guess, though.
 
totoro said:
I have a question concerning F-22's empty weight. It is often cited by various parties to be 19.7 tons.

But looking into the past, weight was much less. There is YF-22, weighing just under 15 tons. And while It was a demonstrator, it was still probably wise to keep it close to final configuration weight. Demonstrating something for one weight and then making another plane that weighs 33% more just doesn't seem wise. X-35 demonstator weighed 12 tons, and final F-35A weighs 13.15 tons. An increase, but not that much of an increase.

And then there is this article: https://www.flightglobal.com/news/articles/f-22-weight-increase-agreed-26820/
which states F-22 (not YF-22) weighed 13,980 kg in 1992 at preliminary design review, and its weight increased to 14,365 kg in 1995, at critical design review. Usually, after a critical design review there is very little changes to the design...

While some may say that the weight did not include various radar absorbent materials, I find that implausible, as not only are they supposed to be part of the plane's structure, but also if RAM is such a huge factor in plane's weight, it would have been part of the calculation to begin with, as such huge differences cause major changes in performance.


So questions are:

How and why did F-22 get from 14,365 kg to 19,700 kg?

And when did that change happen?

These sources might be instructive.

https://books.google.com/books?id=J6BJD1JqDzwC&lpg=PA18&dq=f-22%20weight%20increase&pg=PA18#v=onepage&q=f-22%20weight%20increase&f=false

http://www.dtic.mil/dtic/tr/fulltext/u2/a440032.pdf

https://www.gao.gov/assets/240/233932.pdf

It seems from what little I could gather through these sources, the weight increases continued after critical design review because they kept having to go back to revise the structure of the plane as they were trying to ready it for mass production.
 
At least one weight increase was due to live-fire results. Several spars had to be changed from composite to titanium. (Every 3rd spar or something like that.)
 
totoro said:
I have a question concerning F-22's empty weight. It is often cited by various parties to be 19.7 tons.

But looking into the past, weight was much less. There is YF-22, weighing just under 15 tons. And while It was a demonstrator, it was still probably wise to keep it close to final configuration weight. Demonstrating something for one weight and then making another plane that weighs 33% more just doesn't seem wise. X-35 demonstator weighed 12 tons, and final F-35A weighs 13.15 tons. An increase, but not that much of an increase.

And then there is this article: https://www.flightglobal.com/news/articles/f-22-weight-increase-agreed-26820/
which states F-22 (not YF-22) weighed 13,980 kg in 1992 at preliminary design review, and its weight increased to 14,365 kg in 1995, at critical design review. Usually, after a critical design review there is very little changes to the design...

While some may say that the weight did not include various radar absorbent materials, I find that implausible, as not only are they supposed to be part of the plane's structure, but also if RAM is such a huge factor in plane's weight, it would have been part of the calculation to begin with, as such huge differences cause major changes in performance.


So questions are:

How and why did F-22 get from 14,365 kg to 19,700 kg?

And when did that change happen?

The weight increase is what is allowing the F-22 to serve until the 2050's or whenever the hell I read they were keeping it. Basically it's over engineered and what is available for public consumption says that the F-22s structure is hardly showing any signs of fatigue... That's pretty
amazing, relatively speaking, from the days of the 15 and 16. The 16 was/is so weakly engineered that the Navy had to stop flying 16s as aggressors because the brand new airframes they purchased were wearing out and cracking.

A few years ago there was some information out in the public, circulating, that the 22 pilots would have to go through a series of maneuvers before "dogfighting" in order to warm up the airframes. After reading how well the airframes are holding up, that story was likely not true.
 
Guys, don't forget the FB22 story as well as the end of the Cold War:
- case 1: communality b/w model (bomber and fighter) asked for some beefing-up
- case 2: it became evident that the Raptor will have to survive for a very long time the end of the cold war.
- case 3: a mix of 1&2.
 
TomcatViP said:
Guys, don't forget the FB22 story as well as the end of the Cold War:
- case 1: communality b/w model (bomber and fighter) asked for some beefing-up
- case 2: it became evident that the Raptor will have to survive for a very long time the end of the cold war.
- case 3: a mix of 1&2.

They make the 22 sound so durable that whatever exists of the 187 that does not succumb to a crash will still be available for decades to come. There are a lot of "doors" on the 22 from weapons to landing gear to flare dispensers to the gun to some that are required for startup procedures... I wonder how all those will hold up.
 
Thanks, everyone. latenlazy, your links were especially helpful. There's a very nice graph in the second link, that matches roughly to the known weights we know. YF-22 as starting point (assuming its 14,970 kg is weight without engines) and it matches both the PDR and CDR weights mentioned in that flightglobal article. Since the graph is very explicit in the weight being contractor responsible weight, meaning without the engines, it's very, very likely in my opinion that the flightglobal weights are also without engines.

The graph then states the weight increases up until beginning of 2001. From the PDR and CDR weights, one can calculate that F-22's weight without engines was roughly 400 kg higher than at CDR. Meaning around 14,765 kg.

The last link also gives another increase info. Further set of reinforcements during 2001 added another 129 kg to the airframe. They're likely not in the previous graph as there is no such increase evident. Since 2001 was already pretty far into development and very little changes should have been made from 2002 onwards (preserial production was going on from then on) i find it unlikely there were further big increases in weight. Anyway, contractor's weight should include... what exactly? complete avionics? Does it exclude anything else other than engines? Said weight should be around 14,900 kg.

We have another problem, though. F-119 engines don't really have a clear stated weight. Sometimes a figure of 1800 kg is stated, but I can't find it corroborated by actual manufacturer. Of course, two engines weighing 3600 kg is still quite a bit short of total empty aircraft weight of 19.7 tons. At 18,500 kg, we're short over a ton. So either engines (with whatever ancillary equipment) are heavier, or there's more equipment that's not part of contractor responsible weight that acounts for that ton, or simply some of these publicated figures are wrong. Be it the ones stated for PDR and CDR or the 19.7 ton figure.
 
Short video but all the "pre-designs" flashing in the background is cool

https://www.facebook.com/DeptofDefense/videos/581859548908444/
 
flateric said:

Interestingly, the CAD image shows that several fuselage bulkhead frames behind the radome appear to have a notch cutout at the bottom. Perhaps that is to accommodate the compartment for a chin-mounted IRST? Are there any other diagrams or pictures showing that compartment or what's in it? I wonder if that compartment is still empty or if it has been used for some other purpose.
 
It is a real pity that Lockheed never installed an IRST on the production F-22, I remember having the F-22 ADF flight simulator back in 1997 and that had the IRST featured.
 
<iframe width="560" height="315" src="
" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
F-22 flight envelope sans AB.

There was an article a while back wherein an F-22 pilot mentioned being able to supercruise at sea-level. (Obviously probably not as fast, or as efficiently, as at altitude,)
 
Who were the original developers of some of the key avionics?

APG-77 - Westinghouse/Texas Instruments
ALR-94 - Sanders/General Electric
CIP - Hughes

Who originally developed the AAR-56?
 
Not sure where I heard it, sorry (late 1980s edition of Flight perhaps?). I am pretty sure though that Lockheed Martin is the design authority/manufacturer in the present day (old PDF on their site which unfortunately is no longer available).
 
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I understand that Lockheed Martin is currently owning the AAR-56, but I was asking who the original designer was, as the Lockheed merger with Martin Marietta occurred in 1995, well after Dem/Val and into EMD.
 
It is a pretty safe bet though that LM inherited the AN/AAR-56 via the merger. Also, that II-VI Optical Systems page is probably primarily referring to the pre-merger Martin Marietta element of Lockheed Martin there.
 
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I have a question concerning F-22's empty weight. It is often cited by various parties to be 19.7 tons.

But looking into the past, weight was much less. There is YF-22, weighing just under 15 tons. And while It was a demonstrator, it was still probably wise to keep it close to final configuration weight. Demonstrating something for one weight and then making another plane that weighs 33% more just doesn't seem wise. X-35 demonstator weighed 12 tons, and final F-35A weighs 13.15 tons. An increase, but not that much of an increase.

And then there is this article: https://www.flightglobal.com/news/articles/f-22-weight-increase-agreed-26820/
which states F-22 (not YF-22) weighed 13,980 kg in 1992 at preliminary design review, and its weight increased to 14,365 kg in 1995, at critical design review. Usually, after a critical design review there is very little changes to the design...

While some may say that the weight did not include various radar absorbent materials, I find that implausible, as not only are they supposed to be part of the plane's structure, but also if RAM is such a huge factor in plane's weight, it would have been part of the calculation to begin with, as such huge differences cause major changes in performance.


So questions are:

How and why did F-22 get from 14,365 kg to 19,700 kg?

And when did that change happen?

I’m of the opinion that this is the weight of the aircraft without the engines and perhaps some other equipment. Even during Dem/Val, the estimated takeoff gross weight estimate as 60,000 lbs (an increase from the initial 50,000 lb) and the current one for the F-22A is 64,840 lbs.
 
Hi folks,
I just found this about the Advanced IRST (AIRST or Airstar) at f-16.net.
The USAF has not yet been convinced of the usefulness of IRST, although I have tested the AAS-42 on an F-15 in the late 80's. GE and Martin Marietta Aerospace, which are now part of Lockheed Martin (LMEM) developed an IRST to the ATF program, which became the F-22A Raptor.

The IRST was canceled during the demonstration / evaluation (dem / val). The USAF believes the AN/APG-77 radar capable LPI will be able to meet all your requirements. The space, weight, power and cooling system for the IRST is still in the aircraft.

Still, LMEM won a contract to develop technology for an IRST (AirStar) with potential application in the F-22.

The LMEM tested a Advanced IRST (AirStar) for the F-22. The sensor unit (left) is protected by a window with stealth characteristics (right).

I'm looking at the attached image and I'm not sure what to make of the aperture on the right. Is that supposed to be on the wing root or under the nose? Where did the image come from?
 
Hi folks,
I just found this about the Advanced IRST (AIRST or Airstar) at f-16.net.
[...]
I'm looking at the attached image and I'm not sure what to make of the aperture on the right. Is that supposed to be on the wing root or under the nose? Where did the image come from?
The secondary source of that image, as I wrote back then in 2013, is at the forum f-16.net. Link: http://www.f-16.net/forum/viewtopic.php?p=190627
The primary source, a link or a PDF, have been deleted.
Maybe this PDF might help you:
Source: https://www.forecastinternational.com/archive/disp_old_pdf.cfm?ARC_ID=455[/QUOTE]
 

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I have read in a few sources that Block 40 F-22As would have an "advanced helmet mounted display"
On this episode, the retired U.S. Air Force Colonel Terry “Stretch” Scott describes the Raptor’s amazing features, weapons, performance, and more.
He also helps answer a question on why the F-22A does not have an advanced helmet mounted display (HMD). One reason other than budget just for the insertion of the HMD is that under the slim canopy of a F-22A the pilot has less room to move his head with an HMD safely around. IMHO, when I see the pictures of a F-22, I can't really believe it.
If the USAF really wanted a HMD for the F-22A or for a "F-22C", a new canopy would have been to be designed and tested before, which would have driven up the costs more. So the USAF gave the HMD to the teen-fighters, which really needed them.

Source/Link: https://www.fighterpilotpodcast.com/episodes/061-f-22-raptor/

YouTube:
Code:
https://youtu.be/AguVV7SH9eY?t=3540
 
The HMDCS (now Pilot Systems) was supposed to select an HMD solution in FY19 and take it through a systems level PDR. FY20 would mark the EMD phase of the program with the HMDCS being added to the Block 30/35 Raptor fleet.
 
The F-22's canopy is considerably more tapered than most other fighter canopies for stealth purposes, and I think the polycarbonate material is also thicker as well since it doesn't have a frame and has to endure sustained supersonic flight. Furthermore, the first generation of JHMCS visors did protrude forward from the helmet a fair bit since it's a bolt on addition. Maybe the JHMCS II is a bit less bulky and can fit better, but the best solution would be to have a display system that's incorporated into the base helmet design from the beginning. That's a much more expensive option, however.
 
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F-22 display at Dubai Air Show. Left hand flat spin reversing to right hand flat spin at 3:50 mark. Good camera view of tight back flip at 5:40 mark. Extended vertical pause and back slide at 7:22.

 
As a part of the F-22 Capability Pipeline and through Section 804 Middle Tier Acquisition authority, Sensor Enhancements provides improved sensor capabilities to Block 30/35 F-22 aircraft to maintain air dominance and preserve first shot, first kill capability. Funding includes 143 kits, installation, and spares.

Technology development and demonstration efforts continue for Sensor Enhancements. Enabling Group A kits purchased in FY 2020 to deliver in Q4 FY 2021, while Sensor Enhancements Group B development will mature through FY 2021 culminating in a flight test demonstration late in the FY. A subsequent production decision for Group B hardware will occur in FY 2021.

Volume 2-177 to 2-179



--------------------------------------------------

The average price for the B kit is ~12 M, so expensive. It seems like the AESA upgrade, maybe replace the GaAs with GaN?
 
At this point a clean-sheet design using F119/F135 and the F-35 avionics and sensor suites, would probably be cheaper than restarting the F-22 line.
 
Given the on-going difficulties with the F-35's avionics, it probably would not be a good idea to use them in a new design.
 
The F15 became the air superiority fighter of Japan, Israel and Saudi Arabia. If F22 had been allowed for sale to them it might still have been in production.
 
The F15 became the air superiority fighter of Japan, Israel and Saudi Arabia. If F22 had been allowed for sale to them it might still have been in production.
I think probably Israel, Japan, and the UK are the only ones I'd have felt comfortable with owning F-22. (And I'm sort of on the fence with Japan given their history of giving information to Russia.)
 
The US agreed with sferrin. But even an Israeli buy would have helped. UK had Typhoon and F22 would have been too costly given the post Cold War threat in the 90s. I think Japan could have been risked given its threats fro Rus PRC and NK
 

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