YF-22 vs YF-23

I would suggest there's a LOT more to it (F-119) vs. being just an up rated F-100.

As far as the YF-23A's top speed goes, I'm hearing conflicting things. On the one hand, you say here where it wasn't substantially faster than the YF-22A. Yet in more than one youtube documentary, officials that had worked on the YF-23A said it was a LOT faster vs. the YF-22A.

So who knows what the truth is. I'm leaning toward the fact it was a lot faster, but we'll never know. Let's just hope they do PCA right. I predict Northrup will lead with a scaled up YF-23a type airframe. If so, will be fun to watch the whole thing unfold..

My theory is. Both YF-22 and 23 can go substantially faster than Mach 2.2
Even the F-22's top speed is highly classified.

But going at those extreme speeds compromises the stealth coatings which is why they have an artificial software limit for the top speed. I wonder if they can over ride this in the most extreme emergencies.

Did more digging on the YF-119 vs 120
I read that the 119 did not suffer a single mishap during the DEMVAL phase while the 120 suffered some overheating.

The 119 was also smaller having just 6 stages instead of 10 on previous engines. advanced engine materials and a float wall mechanism allowed the core temperature to reach extreme temperatures which were impossible with previous engines.

If its true that the 119 suffered no mishaps then perhaps the 119 was revolutionary in its own way. Turbine materials that can withstand extreme temperatures and pressures without fail. The 120 on the other hand can't do that.

So are they implying that the F-22 had better acceleration and energy retention numbers than the YF-23. Even if they never flew the 23, I would imagine they have access to the classified E-M charts

How is that implied? YF-23 weight was similar to YF-22 and both have same engines. YF-23 supercruise faster too so how can it accelerate slower? The F-22 pilot is talking about performance he prefers and not specifically about YF-23. Also how would operational F-22 even have YF-23 E-M charts? That makes no sense.

But it would still have better range although I would doubt the production model will retain the range of the YF-23 prototype.

Production models are always heavier than the prototypes so we may be looking at a combat radius closer to 500 or 600 NM rather than the 750- 800 nm

What are you speculating this on? Just because F-22 lost fuel and range form YF-22 doesn’t mean F-23 will. F-22 rear fuselage is much slimmer than YF-22 which reduce drag but also volume and fuel. From diagrams F-23 volume did not change much in fact the fuselage in the middle of wings increased some cross section and volume over YF-23.

Lastly Both the YF-119 and 120 were deemed next generation engines.
We know that the YF-120 used a 3rd stream similar to Advent.

But what about the YF-119, is it just an improved version of the current F-100 series or is there more to it?

YF120 was not three stream it was variable bypass. Their different.

As far as the YF-23A's top speed goes, I'm hearing conflicting things. On the one hand, you say here where it wasn't substantially faster than the YF-22A. Yet in more than one youtube documentary, officials that had worked on the YF-23A said it was a LOT faster vs. the YF-22A.

So who knows what the truth is. I'm leaning toward the fact it was a lot faster, but we'll never know. Let's just hope they do PCA right. I predict Northrup will lead with a scaled up YF-23a type airframe. If so, will be fun to watch the whole thing unfold..

I used to have the presentation where they broke down the DEM/VAL flights for each with the different engines.
That presentation dispelled a lot of rumors. First, that the YF-23 had “much faster” supercruise. It demonstrated faster supercruise but neither the YF-23 and YF-22 reached the Mach 1.72 reported in the F-22’s SAR. Neither exceeded Mach 1.8 in testing either.

Perhaps modeling suggested that the EMD F-23 was capable of higher speeds than the EMD F-22 but it’s really a moot point, it was never selected or built.

I've seen it often stated that the YF-23 was stealthier than the YF-22.

Stealth: Based on the fan blades being exposed from frontal oblique aspect, I don't accept the claims about VLO being better. That was re-designed for the F-23A, but of course never produced.



Speed: If you watch the video with Paul Metz and Jim Sandberg. Paul Metz said they never flew either of the prototypes past Mach 1.85, as the DEMVAL was to demonstrate super cruise in the Mach 1.5-1.8 region, along with maneuvering performance in that flight regime.

Go to 47:00


Maneuverability: The biggest thing I think that gets overlooked is supercruise maneuvering speed vs level flight speed. Everyone gets side-tracked with airshow maneuverability and low speed handling, but one of the main focal points of the ATF was supersonic maneuverability to leap ahead of the Su-27. This is where Thrust Vectoring shows its true advantage, since control surfaces have to be deflected a lot more when supersonic to get the desired response, but when you deflect control surfaces, you get drag.

The question I have is, which design showed better maneuverability at supercruise? The YF-23 has to rely on those huge tails to impart pitch and roll at supersonic speeds from 1.5-1.8 Mach.

Weapons
The next major factor that wasn't known in the open at the time was the limited weapons bay capacity of the YF-23, and even with the F-23A design with an additional bay, it did not match the YF-22's 6 x AIM-120 + 2 x AIM-9X internal stores count. The YF-22 is the clear winner even against the proposed F-23A with lengthened fuselage and additional weapons bay for the 2 x SRAAMs.





Upon learning of some of the more detailed aspects of the program and the YF-23's characteristics, the metric seems to have turned out thusly:

* Speed: YF-23 PAV 2 had ~.25 Mach more supercruise speed with the GE YF120 engines compared to the YF-22 PAV 1 with the same GE engines. Paul Metz and Jim Sandberg describe the speed comparison as engine-dependent, not airframe, with overlap between them. Metz says they never tested the airframes to the full capabilities, and that the YF-23 suffered from canopy cracking at speed ("We would have run out of canopies if we kept testing the YF-23.")
* Supercruise maneuverability advantages are unknown, and will likely remain classified so we don't give any help to China and Russia by saving them the RDT&E time, but the YF-22 used thrust-vectoring while the YF-23 used large tailplanes.
* YF-22 had more internal weapons load capacity with 8 AAMs (6 MRAAM/2 SRAAM) vs the YF-23's 5 AAMs (3 MRAAM/2 SRAAM).
* VLO- YF-23 had exposed engine fans visible to ground radars from a certain aspect. Both had extensive provisions for RF and IR VLO.

Speed: Toss-up according to Metz based on engine more than airframe (both met or exceeded the requirements)
Maneuverability across the flight regime: YF-22 (both met or exceeded the requirements)
VLO in RF and IR: YF-22 (both met or exceeded the requirements)
Internal Weapons Count: YF-22 (which demonstrated carriage and separation of both AIM-120 and AIM-9, even if it was a stunt)

While the YF-23 was a beautiful aerodynamic specimen, it appears that it lost cleanly and fairly to the YF-22 design in most, if not all of the critical metrics for the ATF, while still meeting or exceeding the USAF's performance requirements. The YF-22 just met or exceeded those requirements to a higher degree.

Another thing to remember about Supercruise is that it was envisioned in the 1970s as part of the ATF concept for an F-105, F-4, and F-111 replacement for ground attack, the idea being that Supercruise would allow more survivability when penetrating enemy air defense and still providing enough fuel to have long mission radii.

The ATF program morphed over to an Air Superiority focus with the introduction of the MiG-29 and Su-27, which had what appeared to be really impressive performance, along with large radomes for look-down, shoot-down radars.

Don't forget that NG had a patent on a more compact missile launch system that had the potential of storing 8-12 AMRAAMs internally to the F-23. The space-wasting trapeze was only a backup in case this new way failed.

https://patents.google.com/patent/US4702145

Also the YF-22 was limited to four AMRAAMS in the main bays as the big finned A/B models precluded any additional carriage.

Don't forget that NG had a patent on a more compact missile launch system that had the potential of storing 8-12 AMRAAMs internally to the F-23. The space-wasting trapeze was only a backup in case this new way failed.

https://patents.google.com/patent/US4702145

Seems Rube Goldbergy to me... engineers wanting to piss off Mx staff?

I remember seeing a video out there somewhere on the interwebs (youtube) of Paul Metz talking about both the YF-23 and YF-22. He had a really good quote along the line of

"Northrop gave what the Air Force asked for but Lockheed gave what the Air Force really wanted".

How is that implied? YF-23 weight was similar to YF-22 and both have same engines. YF-23 supercruise faster too so how can it accelerate slower?

Acceleration is not defined by just engines and weight. there are a lot of factors that can come into play, the YF-22 might be better at accelerating at subsonic but looses the acceleration race at supersonic due to supersonic wave drag maybe.
Point is, these are valid questions.

Faster top speeds, faster cruise speeds and faster acceleration are very different things.

Also how would operational F-22 even have YF-23 E-M charts? That makes no sense.

Thats pretty bold. You seem to be absolutely certain they know nothing about the YF-23's performance numbers. So pretty much no F-22 pilot ever talked to Paul Metz or anyone within the USAF ACC and if they did, you're absolutely certain that they were given the same "politically correct" response that they give out to civilians. Cool.

What are you speculating this on? Just because F-22 lost fuel and range form YF-22 doesn’t mean F-23 will.

The fact that the F-22A is 10,000 pounds heavier than the YF-22 maybe. Are we to assume that the YF-23 would have retained the exact same weight from prototype to production and that no design changes would be made?

Acceleration is not defined by just engines and weight. there are a lot of factors that can come into play, the YF-22 might be better at accelerating at subsonic but looses the acceleration race at supersonic due to supersonic wave drag maybe.
Point is, these are valid questions.

Point is, those quote are about the utility of supercruise, not YF-23 vs YF-22 acceleration like you imagine.

Thats pretty bold. You seem to be absolutely certain they know nothing about the YF-23's performance numbers. So pretty much no F-22 pilot ever talked to Paul Metz or anyone within the USAF ACC and if they did, you're absolutely certain that they were given the same "politically correct" response that they give out to civilians. Cool.

Why would F-22 pilots know YF-23 performance numbers? Just because an F-22 pilot talked to Paul Metz means he'll give the whole flight envelope and performance numbers? USAF ACC also NEVER flew YF-23, of 5 pilots that flew only 2 were USAF. ACC and Flight Testing are also completely different branches of USAF and you're just assuming ACC will have access to performance of a prototype that's being flight tested?

Before making so many ridiculous statements read this book first.
https://arc.aiaa.org/doi/book/10.2514/4.867910

The fact that the F-22A is 10,000 pounds heavier than the YF-22 maybe. Are we to assume that the YF-23 would have retained the exact same weight from prototype to production and that no design changes would be made?

YF-23 showed a range and combat radius advantage over YF-22. If you saw F-23 drawings then you see fuselage volume actually increased a bit and was also longer than YF-23. The big humps for thrust reversers are also gone and that volume went to middle fuselage.

As I understand it, that the YF-23 fan blades were visible was irrelevant because you would already be close enough to detect the reflection off the rest of the aircraft if you were viewing it from that angle.
The NG guys seemed sure that their aircraft beat the Lockheed one in everything but post stall, but that MD part of thier team dropped the ball on the manufacturing details.

Point is, those quote are about the utility of supercruise, not YF-23 vs YF-22 acceleration like you imagine.

Thats your interpretation. The YF-23 did have substantially larger wings which translates into more drag when turning. This is why I think the YF-23 would have less energy retention and recovery than the YF-22.

Just like how the F-35C is with the F-35A. Same engine, but bigger wings mean more drag.

Why would F-22 pilots know YF-23 performance numbers?

because they can

YF-23 showed a range and combat radius advantage over YF-22. If you saw F-23 drawings then you see fuselage volume actually increased a bit and was also longer than YF-23. The big humps for thrust reversers are also gone and that volume went to middle fuselage.

So the Super cruise and speed numbers would also be different. and come on, all fighter prototypes are lighter than their production models. why would the YF-23 be different

Thats your interpretation. The YF-23 did have substantially larger wings which translates into more drag when turning. This is why I think the YF-23 would have less energy retention and recovery than the YF-22.

You were talking about acceleration. Also how did you bring turning into all this? YF-23 larger wing area actually result in more lift but lower aspect ratio increase lift induced drag just from the wing, but YF-22 aspect ratio is also low. But how is this related to acceleration? If you want to talk surface area, YF-23 also have 2 tail surfaces while YF-22 have 4 and for stability in testing YF-22 also oversized the vertical tails.

How can you make this comparison and analogy of F-35A vs F-35C when YF-23 and YF-22 fuselage are so different? Did you ever take any aerospace engineering classes? Because I have and you don't just eyeball this kind of thing. Some equations from Raymer or Nicolai approximate simple aircraft but even that is not enough for shapes like YF-23 or YF-22. So how is your eyeball better?

because they can

You clearly don't know how this works. The people in USAF that set requirements are in different section from operational pilots. The customer (USAF) gives the requirement (TRD) for the competing contractors to meet with proposals. In ATF program this included flight demonstrators YF-22 and YF-23. In selection process the board that reviews and select the proposals are again totally different from operational fighter pilots. That's why no F-22 pilot have any reason to know what YF-23 envelope is. Would F-16 pilot know what YF-17 envelope is?

So the Super cruise and speed numbers would also be different. and come on, all fighter prototypes are lighter than their production models. why would the YF-23 be different

Because difference between YF-22 and F-22 is not the same as difference between YF-23 and F-23. You can easily find F-23 drawings. F-22 lost volume over YF-22 especially in rear fuselage and is also a bit shorter. F-23 is actually longer than YF-23 and looking at cross sections the fuselage volume increased especially at middle.

Why are you obsessed with making F-22 best at everything? It's a great aircraft but it's not magically unbeatable.