While the Raptor going mach 3 would be an excellent achievement for a fighter, that is if it could sustain that speed on burner. But it wouldn't be fuel efficient and would emmit a much greater infrared signature though I'm sure mach 2 gives off enough of one. And I believe the wind speed at mach 3 would be detrimental to the stealth material on the body of the plane, someone correct me if I am wrong.

No, you are mainly correct but that is why the Raptor wouldn't go that fast. It simply isn't a mach3 design aerodynamically (the big boxy fuselage cross section and intake design sees to that) and it would only ever go to mach 2 as a last resort, which would make stealth considerations academic in any case. Thats why the Raptor supercruises around the mach1.6 mark, the drop off in efficiency as you go faster is out of all proportion to the speed gained.

Originally posted by grunt2
1)the plane isnt superfast, its supercruiser and supersonic lift
2)the difference between supercruiser and max speed isnt sooo big, mainly because the engine is a high dry thrust -as someone explained before-

the links are there

AMM, again you are again speculating

but nothing he has said has even made me consider the idea that the Raptor could not obtain a speed of Mach 2 with afterburner and Mach 1.8 in supercruise.

yes,yes, because is a national symbol

Ha! I used the same arguement about the Spitifire... funny... but yours is incorrect. I think the last plane seen as a national symbol by America is the B-2 Spirit of America, hence the name.

But about the F-22, it's actual top speed is classified.

How much faster it could be, probably not to much, but enough to make a difference on gussing attack times by such an aircraft.

I have a friend who is a test pilot for the F-22. We have talked about it's abilities, but never about it's true top speed. The speed isn't what makes it great.

It's the technology! The avionics! (which I used to fix for the US Military)
Also, the military will pay for the cheapest product that can get the job done and not go overboard. For example, the YF-23 was a more powerful plane, and more expensive...

But more importantly, as my dad used to say (former Navy Attack Sub engineer),

"You'll never know it's top speed. If you do, they have something better."

Here is my ultimate theory

The top speed is probably not that much higher than released to the public.
The only reason it seems to be a "national symbol" is because it's really a diversion. There is clearly another plane in the works or already developed which out performs the F-22.

It's a common tactic by the U.S. Government... look here in my right hand, while I perform the magic trick with my left...

But I suppose that can be considered speculating....

What I can tell you is the F-22s released top speed is NOT it's true top speed. It is probably faster... but could also be slower! (The Russians used to use that tactic a lot) But regardless, it's not it's true top speed.

If anything I could ask my friend, but he is in another state now, so I would have to wait until we meet in person... cause you just don't talk about those things in email or over the phone... cough...

---Cheers---

I have seen it mentioned before about the Raptor being used as a sort of cover for something better, but I don't really see how that can be the case. Of course there could easily be something better in development (I mean easily in a political sense, not a technological one) but seeing as the Raptor is to be the main air defence fighter of the USAF how would you secretly deploy a superior type? And why? That would make the Raptor a colossal waste of money, unless this 'superior type' was actually its successor. In which case it could not remain secret for very long. Its not like a spy plane where there are relatively few and there is no 'presence' to maintain. I know the F-117 was deployed in secret but only 59 of those were built, which is kind of the point I am trying to make.

It doesn't matter how much better a plane you've got if your fighter pilots are flying the Raptor anyway, if all the Raptors suddenly disappeared because their crews converted to a secret replacement it would be kind of obvious, yes? Any ogf that make sense?

BTW, have another look at the Spitfire discussion (if you haven't already), I discovered some interesting comparisons between the planes we were discussing.

Originally posted by waynos

BTW, have another look at the Spitfire discussion (if you haven't already), I discovered some interesting comparisons between the planes we were discussing.

Sorry I respectfully removed myself from that circular discussion.

About my "theory",

I have noticed a pattern with military projects in my short career. My dad did, and so did my grandfather.

There is always something better. The ATF program created in 1981, also called Senior Sky, was designed to replace the F-15... the F-22 is just now being 'produced'...

wow! I just read this:

"After Lockheed was announced as the winner, Skunk Works largely backed out of the F-22 program and left it, as tradition dictated, to the mainstream Lockheed organizations in Marietta and Fort Worth...They will still provide engineering and technical support as needed, but another fighter project had already begun at Skunk Works." -- "Lockhed Secret Projects" author D. Jenkins

I could break down all your questions/statements but the above quote made my point. Skunk Works doesn't stop. JSF has been passed off, x-33 and Darkstar are canceled... I guess we need to send the Engineers home.

I don't think so But I guess this would be a discussion in a whole new thread.

Originally posted by rmatrem

Sorry I respectfully removed myself from that circular discussion.

Fair enough, its a free choice, I just thought you might be interested in some of the stuff we've discussed since you left (still about the Spit and P-51), no worries

There is always something better. The ATF program created in 1981, also called Senior Sky, was designed to replace the F-15... the F-22 is just now being 'produced'...

Oh yes, I agree absolutely. My apologies, I thought you were saying it was maybe a cover for something else serving alongside it

wow! I just read this:

"After Lockheed was announced as the winner, Skunk Works largely backed out of the F-22 program and left it, as tradition dictated, to the mainstream Lockheed organizations in Marietta and Fort Worth...They will still provide engineering and technical support as needed, but another fighter project had already begun at Skunk Works." -- "Lockhed Secret Projects" author D. Jenkins

Just searched and found that book on Amazon, thatnks for the heads up

[edit on 17-11-2005 by waynos]

BTW, the Federation of American Scientists is a private organization. Aeroflight is an aviation enthusiast site. And POGO is a private lobbying group against government spending.

None are "official" in any sense of the word.

If someone wants to sort this out ->

1. Get a picture of the planform of the F-22.
2. Draw a line from the nose to where it meets the wing/body only once (it'll be the intake forebody or the wingtip)
3. Measure the angle between this line and the aircraft centreline (we'll call it beta)
4. Design Mach number = 1/[sin(beta)]


Its that simple.



I also know they reduced the sweep of the wing leading edge for better low speed handling [YF-22 to F-22A], whether that infers a lower than expected top speed [enabling them to change the LE sweep angle without penalty] or not I don't know.



Edit: From a dodgy picture I guesstimate at a design cruise Mach number of 2.15 if the probe extending from the nose is not included. (Mach 2.3 if the probe is included)

I'll stress again, its a dodgy picture and I'm running rough figures off a ruler.

But I'll safely rule out Mach 3 flight and be confident in putting an upper limit of Mach 2.5 on its Vmax.

[edit on 14-6-2006 by kilcoo316]

The F-22 has F119 engines which are optimized for raw power and economy, not all out speed. Compared to the older F100 engine used in the F-15 which where optimized for mach numbers. Think of it as the F119's move more air (producing more lbs of THRUST) slower, and the F100's move less air (producing less lbs of thrust) FASTER. The F-22 isnt made to be a blackbird or even an eagle, its stealth and weaponry give it the advantage of not having to rely on speed to come out on top. And just because all the facts arent being released doesnt mean theyre really outrageously extraordinary, it just means the war planners on our side want to keep as much of the advantage as they can.

It's come to my attention that many people don't know about the design of the F-22's intake system. Although the intakes are fixed, they are of a very complex technology. Engineers have basically rendered the variable geometry intake useless. Besides, they didn't make a difference under wartime operations. The F-15C can get to about Mach 1.8 with a full load-out of 8 missiles. I believe the F-22 can do about Mach 2 to Mach 2.2 with afterburners safely without any damage to the airframe. Top supercruise speed is around Mach 1.5-1.7. Either way, the plane is very, very quick. It will acclerate away from an F-15C in full AB on just full military thrust.

Here's how a member of f-16.net explains it:


Just because the inlet on the F-22 doesn't use 40 year old technology of hydraulically powered ramps like an F-15 doesn't mean it isn't as good or better.

Modern inlet systems do not have to physically change geometry to provide optimum pressure recovery for the engine. Traditional supersonic inlets have moving ramps, cones or other devices to capture the normal shock in the inlet throat and alter capture area. The F-22 inlet system does the same thing without traditional moving parts. No moving parts makes RAM treatments inside the inlets more durable and reduces RCS.

Like old technology inlets, each F-22 inlet is spaced away from the forward fuselage to form a boundary layer diverter. This prevents low energy turbulent air from entering. The F-35 uses the fuselage "hump" in front of the inlet to accomplish the same purpose.

The upper inboard corner of the F-22 inlet lip creates a series of oblique shocks. Air is slowed by passing through those shocks and is compressed in an external 3D compression ramp before entering the inlet throat.

In the inlet throat, a sophisticated porous plate bleed system traps a normal shock and airflow becomes subsonic. The bleed system dumps overboard through the parallelogram-shaped door on top of the fuselage about 3 feet behind the upper inlet lip.

Pressure increases as subsonic airflow passes through a gradually diverging duct with a 6:1 length-to-engine face diameter ratio. The 6:1 ratio assures uniform airflow quality at the engine face.

Any excess airflow is dumped overboard through a hexagonal grid on top of the fuselage near the wing root. The bleed and dump functions are controlled by the integrated flight and propulsion control software in a CIP.

This technology was demonstrated in the YF-22s and is repeated in the F-22A.

The bottom line is that the 3D aero pressure recovery in an F-22 inlet is superb and one of the factors that allows it to supercruise at 60+K feet.

Hint: The M 2.0 limit is due to materials used in the wing leading edges, not by the propulsion system.

[edit on 18-6-2006 by JFrazier]

Well I guess that's not classifed anymore....

Your source at the F-16 forum is right on the mark. I would disagree with the top speed but it's not worth arguing the point.

Intelgurl~

Not sure if anyone is still interested as these posts are a year old (I just discovered this site...

The F22 is unlikely to be a beyond M2.3-2.5 aircraft because of the use of composites which are temperature sensisitive an the overal configuration of the aircraft (wing sweep etc)

Interestingly, Concorde has been supercruising for 30 years until retirement while carring 100 people! It only used reheat to go supersonic and then cruised dry at M 2.0. (Took it NY to London once-Fantastic!)

The F111 (particularly the F model but even lower thrust versions) was capable of speeds in excess of M2.6 with the only limitation being temperature rise on specific airframe parts. It had a warning system to indicate the need to reduce speed due to this. A number of unofficial dash flights were done by RAAF F111Cs over the years where they briefly exceeded M 2.65 but they can cruise in low zone burner for long periods supersonically.

naked leadrer.f111.
2.5, 1,855 mph (2,985 km/h)
thats the speed i got
and the mig 25 foxbat.
at an alltitude.
2,110 mph (3,390 km/h) at 42,650 ft (13,000 m), Mach 3.2 [clean]
1,865 mph (3,000 km/h) at 42,650 ft (13,000 m), Mach 2.83 [loaded]
at sea level: 650 mph (1,050 km/h), Mach 0.85


[edit on 20-9-2006 by phsyco]

Originally posted by rmatrem
What I can tell you is the F-22s released top speed is NOT it's true top speed. It is probably faster... but could also be slower! (The Russians used to use that tactic a lot) But regardless, it's not it's true top speed.

yeah and why would any military give out there secrets.i mean they would make there enemy afraid of the planes or any machinerys performance.now ill go with
rmatrem

~~~~~~~~~~~~~~~~~~~~~~~~~
Mod Edit - trimmed big triple quote

Please trim those quotes down to the specific bit you are responding to.

Thanks

[edit on 20-9-2006 by masqua]

IG,

>>
The Lightning's initial rate of climb was 50,000 ft per minute.
>>

Depends on the variant. By the time they made them useful (pull guns, add gas, add IFR probe) around the F.4/F.6 it was actually a bit of a tank according to Aggressors flying out of Alconbury.

>>
Compare that to the Mirage 111 which could climb at 30,000 ft per minute.
>>

Better actually, with the SEPR rocket pack. Mind you, at the time the USAF was still flying B-57s in the low altitude intruder role from French bases and the Russians were practicing the same in their Beagles so what the hell exactly they thought they were proving...

>>
The F-4 Phantom did 32,000 ft per minute
>>

More like 24-27,000fpm. Nekkid. Of course the F-4 was aboult as useless as pig on roller blades above 20,000ft anyway and had this peculiar habit of crippling itself with centerline tank jettisons above 300 knots.

>>
The MiG-21 managed to go 36,090 ft per minute
>>

Not operationally. The early models didn't have the thrust or the inlet scheduling to hold the Mach point with the R-11. The later Bis/N with it's R-25 sucked gas like a drunk in a brewery to gain back the T/Wr that the added avionics and fuel weight in the bigger spines required to compensate for the initial CG problem. The MiG-19 is a better fast-rise interceptor than the MiG-21, simply because it is an honest one which doesn't pay the price of a snapup from an initial acceleration sprint to get the weight down for a topout that is going to be fuel critical.

>>
The rate of the F-16 was 40,000 ft per minute
>>

The YF-16 maybe or a clean IPE/EFE bird. While the LGPOS has more fraction than most in it's class, it frankly doesn't accelerate well through the Mach thanks to the design of the LERX and this makes it suffer a lot in a non Rutowski profile.

>>
And the Tornado can climb at 43,000 ft per minute
>>

The RB199 suffers _a lot_ above about 15,000ft as the tri-spool configuration just wheezes out on compression. The Fin's got good coefficients but between fuel tank issues and wingloading...

>>
The Lightning held that record for a long time and initially beat out the F-15 - although supposedly the F-15 and Mig -25 were finally able to beat the Lightning's world record.
>>

And the Lightning was good for CAPing the outer marker. If you had a tanker and SAR handy. The Bloodhound had a greater combat radius. As I recall, we ran the numbers and came to the conclusion that the E-266 was probably rocket augmented and while the Streak Eagle would beat a Saturn V to about 30-32K if I remember right, it was another nekkid-is-as-hands-over-crotch-does platform.

>>
Seeing how the F-22 Raptor is known to climb from the deck in the supersonic regime, I doubt that the Lightning has it beat. I am certainly open to enlightenment on the subject, I sure don't want anyone to think I am a Raptor "fanboy".. or girl as it were...
>>

I've seen the 'up, up and away!' climbout video of the Lightning and it is indeed impressive for the (early 70's) timeframe as you see the double-dots of the engines go lumbering down the runway for a goodly distance before the airframe goes planform with that arrowhead shape and then ramps away upwards. That said, it is not terribly energetic in subsequent acceleration and I doubt /seriously/ the attitude is held to more than a 10-15,000ft topout as a function of typical Viking Profile showmanship launch.

After which, the aircraft will promptly glide back. Whether the pilot is still attached or swinging beneath the silk escalator depends on how drunk he is.

>>
From what I've heard from a couple of Eagle drivers (obviously not all F-15 jocks would do it this way), in order to climb supersonic, they take off in the F-15, climb to around 20,000 ft and then go into a slight dive to achieve Mach 1+ and then go back into the climb in the supersonic regime. This is apparently quicker than staying on the deck and hitting Mach 1, then climbing.
>>

This is the profile used for the Streak Eagle on some of the higher record attempts.

Lower down (15-25,000ft class), they had to use a giant alligator clip and a tank as a hold back device just to let the pilot run up to Stage 1 and once he was off to the races, the bird was off the ground in only about 500-700ft, faster than they could get the gear retracted in full burner, even with the nose going pure vertical. With that kind of smash; I doubt if excess stick wiggling does anything but hurt you before you pass through the bar height.

For the higher runs I believe there is also a ramp recovery variable involved and at least on the early -100 engined birds, once you hit a given Mach point a secondary 'War Emergency' (VMAX) type button on the left console gave the jet a number of minutes at higher pressure/temp/rpm combination.

Supposedly it really made the Eagle scoot. When Nekkid. As an indication of how much wear and tear it involved, it was also strictly forbidden to use in peace time as they had to pull and inspect plus retune the mechanicals on the engines afterwards.

I understand the 220E mod removes the feature in turn for a general flat rating under a DEEC so whether this means the current C-Eagle is better or worse I don't know for sure. My understanding is that an Albino with uprated engines is about the equal of a 229 Mudhen with CFT but no LANTIRN or bombs.

>>
Also I understand from both Eagle and Falcon pilots who have run chase for Raptors, that the Raptor walks away from them whether in a climb, level flight or whatever.
>>

Hauling 2-3 tanks to have adequate chase time? I'm not surprised. Put a pair of EFE engines into an F-15 in particular and it would likely stay in the game quite handily _at equivalent fuel weight_.

They really shouldn't lie about the Raptor like they do in comparison with tired red and white teeny jets filled with instrumentation from a dozen other programs. It's not the sprint, it's the lope, where the F-22 really steps out.

>>
It must be hell for a pilot to retire and go from flying a fighter to flying an Airbus for Federal Express.
>>

Yeah wasting all that gas. Losing all those wars. And then they get a guaranteed cushy 60 grande a year golden parachute into the mailtube-with-wings meal ticket industry. Just absolutely sucks to do an outdated job at union rates.

Note that whenever you sacrifice the ability to go futhest with the mostest, you automatically pick up quite a bit of 'fustest' performance. Kind've like a cafe racer next to a tractor trailer rig. Except the Tractor Trailer still gets four Sparrows and twelve Mk.82 to shoot your ass down from 10 miles out before bombing your runway.

Mind you, there is not an Airbust or 'Boing' on the planet which will not out climb, out ceiling and out accelerate any armed fighter on the planet /other than/ the F-22. In military thrust.

Fighters are one-shot worthless.

CONCLUSION:
There's a book you might want to pick up by Bill Gunston I think it was. _Fighters Of The Fifties_. Covered the Draken, Mirage, Ford and Lightning among others. Gives some interesting insight into what made a hotrod in those days and a few of the quirks that went with it (F4Ds with engines backfiring 'blue flames' out through the inlets on startcarting on a wet deck. Being stuck in the clag at the top of a failed attempt to climb out of the weather with ice on the wings and bingo fuel light blazing away like Rudolph, 40,000ft over the Sea of Japan with a Bear 'somewhere near enough', as to make the cockpit shake with turboprop noise and utterly invisible for all that. Fogged over canopies leaking mist that lead to /internal/ icing of the cockpit due to sudden altitude changes not being within the range of the pressurization system as you came back down looking for the boat. Oh yeah, that's Riley for you. Him, his sainted widow and their four Irish Catholic brats.).


KPl.