F-22 Comparison

The F-104, XF8U-3 and for that matter the Mirage III all had centerbodies in
their inlets to generate a second shock located near the inlet lip. In the
case of the F8U-3, the centerbody was the radome.

A non movable centerbody ie. a fixed inlet.




While I'm with you that
Metz is in the best position to know, I will be fascinated to learn how a
M2.5 inlet with decent pressure recovery works without some sort of second
shock generator in the inlet. The inner wall of the inlet (with the boundary
layer splitter) may form a fixed shock generator since the inlet lip of the
F22 is "swept" back WRT the splitter.



Beats me but both the Crusader 3 and the F-22 have vents to dump
excess air overboard at low speed. One thing I find interesting about
the F-22 is if you notice in almost every picture taken from chase
aircraft it's got it's flaps partially down.

On Sun, 30 Nov 2003 18:06:01 -0500, "Paul F Austin"
wrote:

The F-22 is certainly the
fastest airplane in the world with anything more than a tank full of cannon
ammunition and possibly a pair of wing-tip missiles.

Surprising to encounter such a statement from someone who usually is
fact based. Do we forget the missile bays?

If the point is "air dominance fighter" and the speeds are set with "a
tank full of cannon ammunition" and a half dozen IR and radar guided
missiles, oriented by a data-sharing system of three-dimensional
sensor integration, what more do you seek?

I'm beginning to feel like I'm in the Republican Party in which, if
the candidate is not ideologically pure, we must self-destruct to show
the total commitment to the cause.

Gimme a break. The F-22 is an aircraft in development. It is flying
and it is proving. It competes with other systems. It is more or less
expensive, depending upon the accounting criteria used to measure unit
cost. We've done well with F-15 over thirty years and we've done well
with Viper (although the numbers aren't quite as compelling.) If we
compare with what the "woulda, shoulda, coulda" numbers for the Soviet
wunderkind are we generally come out on top.

If we improve US indigent health care at the sacrifice of next-gen
tactical aircraft, will we be better off? I'm betting on the
techno-iron as the better spending choice.

On Sun, 30 Nov 2003 18:06:01 -0500, Paul F Austin wrote:

There've been a lot of religious arguments here about what "true
supercruise" is and what airplanes can do it and it plainly has to mean
"with ordnance aboard" or it means nothing at all. The F-22 is certainly the
fastest airplane in the world with anything more than a tank full of cannon
ammunition and possibly a pair of wing-tip missiles.

SR-71? MiG-25/31?

--
"It's easier to find people online who openly support the KKK than
people who openly support the RIAA" -- comment on Wikipedia
(Email: , but first subtract 275 and reverse
the last two letters).

In article ,
ess (phil hunt) wrote:

On Sun, 30 Nov 2003 18:06:01 -0500, Paul F Austin
wrote:

There've been a lot of religious arguments here about what "true
supercruise" is and what airplanes can do it and it plainly has to mean
"with ordnance aboard" or it means nothing at all. The F-22 is certainly the
fastest airplane in the world with anything more than a tank full of cannon
ammunition and possibly a pair of wing-tip missiles.

SR-71?

Not a lot of guns in SR-71s, and the YF-12s aren't even in existence any
more, right?

MiG-25/31?

Once you load a couple of missiles on the wings, the MiG slows down a
*lot*. That Mach 2.8 speed mark it set was completely clean, no
weapons. And if you stick a full combat load on it, you're getting down
into the Mach 2 range...

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

All wrong about MiG-25/31. Due to ingenious design and engines that produce
50% more power dynamic thrust then static, MiG-25 aircraft have the
max -loaded- speed of M=2.83 at height, and because of humongous power of
MiG-31 engines, MiG-31 can do the same. Mig-25RB can also carry four BOMBS
up to M 2.83! MiG-31 also has the datalink that doesn't still exist in
Westrn aircraft, so they have sensor fusion (lead aircraft receives data
from other three aircraft in 100 km spread) and aircraft can "take over"
guidance of the missile among each other.

At this point, I would like to de-mistify the claim that MiG-25, if flying
beyond M3 must have engines replaced. The exact words of Rostyslav Belyakov,
chief eneneer are "Going beyond M3 does not produce any damage, but reduces
lifetime of the airframe". So, leave the MiG-25 engines alone.

--

Nele

NULLA ROSA SINE SPINA
Chad Irby wrote in message ...
In article ,
ess (phil hunt) wrote:

On Sun, 30 Nov 2003 18:06:01 -0500, Paul F Austin

wrote:

There've been a lot of religious arguments here about what "true
supercruise" is and what airplanes can do it and it plainly has to mean
"with ordnance aboard" or it means nothing at all. The F-22 is certainly
the
fastest airplane in the world with anything more than a tank full of
cannon
ammunition and possibly a pair of wing-tip missiles.

SR-71?

Not a lot of guns in SR-71s, and the YF-12s aren't even in existence any
more, right?

MiG-25/31?

Once you load a couple of missiles on the wings, the MiG slows down a
*lot*. That Mach 2.8 speed mark it set was completely clean, no
weapons. And if you stick a full combat load on it, you're getting down
into the Mach 2 range...

--
cirby at cfl.rr.com

Remember: Objects in rearview mirror may be hallucinations.
Slam on brakes accordingly.

On Mon, 1 Dec 2003 09:50:56 +0100, "Nele_VII"
wrote:

All wrong about MiG-25/31. Due to ingenious design and engines that produce
50% more power dynamic thrust then static, MiG-25 aircraft have the
max -loaded- speed of M=2.83 at height,

That's a fantasy. Throw four AA-6s on there (full load) and it won't
even come close to that.


and because of humongous power of
MiG-31 engines, MiG-31 can do the same. Mig-25RB can also carry four BOMBS
up to M 2.83!

IIRC it's more like 2.6 and it's four bombs in two lines of two which
means a lot less drag than four AA-6s




At this point, I would like to de-mistify the claim that MiG-25, if flying
beyond M3 must have engines replaced. The exact words of Rostyslav Belyakov,
chief eneneer are "Going beyond M3 does not produce any damage, but reduces
lifetime of the airframe". So, leave the MiG-25 engines alone.

Maybe you could explain why no Mig-25s ever got close to a Blackbird?

"Ed Rasimus" wrote in message
...
On Sun, 30 Nov 2003 18:06:01 -0500, "Paul F Austin"
wrote:

The F-22 is certainly the
fastest airplane in the world with anything more than a tank full of
cannon
ammunition and possibly a pair of wing-tip missiles.

Surprising to encounter such a statement from someone who usually is
fact based. Do we forget the missile bays?

If the point is "air dominance fighter" and the speeds are set with "a
tank full of cannon ammunition" and a half dozen IR and radar guided
missiles, oriented by a data-sharing system of three-dimensional
sensor integration, what more do you seek?

Ed, sorry if I expressed myself badly. That's entirely my point. The F-22
makes its maximum Mach number (for what that's worth tactically) will a
suite of six AAMs. The comparable numbers for Typhoon, Su-37 or just about
any aircraft built since the F-106 are for a clean airplane. I'm willing to
speculate that they can make M2.5+ with an AAM on each wingtip and a tank of
cannon shells but certainly not with all the hardpoints filled.

In any case, history has shown that the utility of the maximum Mach number
is *severely limited* if the persistence is measured in handsfull of
minutes. That's the whole reason for sizing the airflow and dry thrust of
the F-22 to power Mach 1.7ish flight for 30 minutes or so and the reason we
talk about "supercruise".

Inter-aircraft data sharing is going to revolutionize AA combat (for
everyone except the Swedes, who've used it for about forty years). With an
LO airframe and integration with the Rivet Joint a few hundred miles back,
not to speak of overhead assets, fighters will have the conspicuity of
submarines combined with -somewhat better- mobility.

"Scott Ferrin" wrote in message
...
On Sun, 30 Nov 2003 17:44:46 +0200, "Yama"
wrote:
I am sceptical.

Maybe you missed that last line. Paul Metz is the chief test pilot, I
think he'd know.

I'd also think that he is not allowed to distribute still unreleased flight
performance data.

oesn't F-22 have fixed intakes? Speeds over mach 2.0 are
pretty much impossible to attain with fixed intakes.

Despite what much of the media would have you believe fixed inlets
mean zippo.

No, they mean very much. It is certainly POSSIBLE to make a mach2+ plane
with fixed intake, but this will do very bad things to inlet performance in
other speeds (which are considerably more important). All your cited
examples are such cases.

esides, such speeds
require some special materials in radome

The YF-12 of the sixties had a radome that was good for at least Mach
3.2


canopy etc.

The F-15 was originally going to be designed to reach Mach 2.7 but
when they decided to go with the acrilyc canopy they had to back it
off to 2.5. I find it difficult to believe that haven't figure out
how to make one a tad better at high speeds in the past 30 years.

See above. It comes down to what is possible and what is sensible. If
solving problems of Mach2+ flight regarding *serviceable combat aircraft*
was so trivial as you make it sound, each and every modern fighter plane
would go Mach3 or more. Engine thrust has not been a limiting factor in
fighter top speed in like 40 years. In addition to that, F-22 also has
considerable stealth requirements. Radar-absorbing paints for example may
not be very tolerant to high speeds.

What I've seen for F-22 speeds as in combat configuration are mach
1.4-1.5
with supercruise,

It's hit 1.7 that they've released.

In what load configuration?

Ed, sorry if I expressed myself badly. That's entirely my point. The F-22
makes its maximum Mach number (for what that's worth tactically) will a
suite of six AAMs.

Eight. Six AIM-120s and 2 AIM-9s (minor nit pick :-) )

Maybe you missed that last line. Paul Metz is the chief test pilot, I
think he'd know.

I'd also think that he is not allowed to distribute still unreleased flight
performance data.

Which is why he said the maximum speed is classified. Did you even
read what he said?




oesn't F-22 have fixed intakes? Speeds over mach 2.0 are
pretty much impossible to attain with fixed intakes.

Despite what much of the media would have you believe fixed inlets
mean zippo.

No, they mean very much. It is certainly POSSIBLE to make a mach2+ plane
with fixed intake, but this will do very bad things to inlet performance in
other speeds (which are considerably more important). All your cited
examples are such cases.

Actually the Crusader III was excellent at low speeds as is the F-22.
Optimizing an inlet for subsonic speeds but making it able to reach
supersonic speeds presents one set of problems. Optimizing for
supersonic speeds but making it efficient at low speeds presents a
different set of problems. They are not identical.


See above. It comes down to what is possible and what is sensible. If
solving problems of Mach2+ flight regarding *serviceable combat aircraft*
was so trivial as you make it sound, each and every modern fighter plane
would go Mach3 or more.

Where did I say that or even hint at it?


Engine thrust has not been a limiting factor in
fighter top speed in like 40 years.

Dry thrust certainly has been.


In addition to that, F-22 also has
considerable stealth requirements. Radar-absorbing paints for example may
not be very tolerant to high speeds.

You mean like the stuff that was on the Blackbird?




What I've seen for F-22 speeds as in combat configuration are mach
1.4-1.5
with supercruise,

It's hit 1.7 that they've released.

In what load configuration?

No external stores. They didn't say what they had inside. Could be
they had a full load of fuel and test shapes for missiles or they
could have had minimal fuel and nothing in the missile bays.