Jet fighter top speed at military power

I am wonderning what the top speed (in mph) a clean F-15C, Mirage
2000, F-16C, and MiG-29 could accelerate to in level flight at optimum
altitude (not just sea level) without afterburner. I usually see the
top clean speed and the top sea level speed (with afternburner?)
quoted, but rarely the top military power speed.

If there are any online references for non-afterburner speeds of other
supersonic jets, I'd be interested to know where to find them!



Secondary question: did the F-15 get faster recently? Reference books
of a decade or so ago tended to quote 1650 mph as top speed in clean
configuration ion a good day (etc.) but now I see figures of 1875 mph
on USAF web sites.

Any help would be appreciated.

On 27 Nov 2003 03:54:51 -0800, (David L. Pulver)
wrote:

I am wonderning what the top speed (in mph) a clean F-15C, Mirage
2000, F-16C, and MiG-29 could accelerate to in level flight at optimum
altitude (not just sea level) without afterburner. I usually see the
top clean speed and the top sea level speed (with afternburner?)
quoted, but rarely the top military power speed.

If there are any online references for non-afterburner speeds of other
supersonic jets, I'd be interested to know where to find them!



Secondary question: did the F-15 get faster recently? Reference books
of a decade or so ago tended to quote 1650 mph as top speed in clean
configuration ion a good day (etc.) but now I see figures of 1875 mph
on USAF web sites.

You would probably need to have the -1-1 charts to get a number. Since
you specify "optimum altitude" the number wouldn't give you a
comparison between aircraft. My suspicion (and it has little more
going for it than that) is that with modern engines and low-drag
shapes, the number will be pretty close to .95 mach for each. The
governing factor isn't the thrust or drag so much as the transonic
shock wave with associated high drag rise. Once supersonic, many of
those aircraft could ease back out of reheat and stay super for a
while.

As for the two top speeds, it looks at a glance like the difference is
pretty close to the difference between knots and miles/hour.

"David L. Pulver" wrote in message
om...
I am wonderning what the top speed (in mph) a clean F-15C, Mirage
2000, F-16C, and MiG-29 could accelerate to in level flight at optimum
altitude (not just sea level) without afterburner. I usually see the
top clean speed and the top sea level speed (with afternburner?)
quoted, but rarely the top military power speed.

If there are any online references for non-afterburner speeds of other
supersonic jets, I'd be interested to know where to find them!



Clean F-15C, F-15E, F-16s with -220, -229 engines can hold .98 to .99 Mach
in Mil power..

On Thu, 27 Nov 2003 16:04:29 GMT, Ed Rasimus wrote:

You would probably need to have the -1-1 charts to get a number. Since
you specify "optimum altitude" the number wouldn't give you a
comparison between aircraft. My suspicion (and it has little more
going for it than that) is that with modern engines and low-drag
shapes, the number will be pretty close to .95 mach for each.

That wouldn't surprise me at all.

--
"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).

Don't know about the new stuff but an F104A with the J79-19 engine was
good for .97M at sea level and would accelerate to 1.05M in honest to
God level flight at 25,000, all in military power (non-AB). Did it
myself.
Walt BJ

The F-15C has better engines than the
F-15A. Maybe that is the cause for
the discrepancy.

I think its like this:

A- 25,000 lbs each
C,E- 29,000 lbs each

Nope. Only some of the E's have the IPE (PW-229). The remainder as well as
all the A's through D's have PW-220s or PW-220Es (except for the C/D's at
Langley, Eglin, and Tyndall, and several A/B ANG units that still use the old
PW-100s).

During flight test the clean E with PW-229s easily cruised above M 1.0 at mil,
whether accelerating up to it or decelerating down to it. It is not likely the
fully loaded E can do this.

During flight test the clean E with PW-229s easily cruised above M 1.0 at
mil,
whether accelerating up to it or decelerating down to it. It is not
likely the
fully loaded E can do this.

By clean, do you mean w/o conformal tanks? By easily cruised, do you mean
accelerated through mach w/o resorting to A/B? Is this based on personal
experience?

I have little doubt the clean F-15E can sustain 1.2 give-or-take in mil ...
but the acceleration through transonic might be a problem. By the same
token, the F-14B/D's can also supercruise, but they need A/B to get there
first.

The difficulty is handling the transonic drag rise, largely a function of
the design drag characteristics of the jet. Low aspect ratio, area-ruled,
thin-winged aircraft tend to do best (think F-104, Mig-23). Drag rises
sharply starting around .92 or so and peaks around 1.1-1.2. Most aircraft
run into a wall here (particularly at military thrust) and the difference in
speeds attained is remarkably little (I found the F-8 to be a wee bit faster
in military than the F-4, but I never flew the older and cleaner Phantoms
.... the F-4H1 was reputedly good for 1.04 or so, similar to F-104). And
recent designs have generally abandoned minimum-drag configurations to
attain other, more useful, characteristics.

A/C top speeds are illusory ... sometimes I think they're based more on what
comes from marketing than engineering. The F-14 was attributed with 2.34
(it attained 2.41 ONCE in flight test and was artificially limited to 1.88
in the fleet ... though it got there easily enough). The F-18 has a 1.8
claim ... I know NO ONE who's seen close to that (so maybe once in flight
test?). The F-15 is always attributed with 2.5/1650mph ... again maybe once
in flight test? (The PsubS curves I've seen would suggest otherwise, and
perhaps nobody told them about what happens to plexiglas at those speeds.)
Of course when you hang some ordnance, drag goes up and speed goes down ...
sometimes dramatically.

If one restricts the argument to military thrust only, top speed ranges from
..92 or so (low thrust or high drag limited) to maybe 1.04. Not much of a
difference if you're trying to outrun an AIM-120.

R / John

Thanks for the responses!

A/C top speeds are illusory ... sometimes I think they're based more on what
comes from marketing than engineering. The F-14 was attributed with 2.34
(it attained 2.41 ONCE in flight test and was artificially limited to 1.88
in the fleet ... though it got there easily enough). The F-18 has a 1.8
claim ... I know NO ONE who's seen close to that (so maybe once in flight
test?).


Sometimes I wonder if the marketing guys just go something like "well
it's got a thrust to weight of X, it's got them there fixed intakes so
it's automatically less than two, and it's not quite as streamlined as
an F-16, let's slap '1.8' on it and call it good".

Any 4th generation aircraft with fixed intakes is automatically
assigned 2 or less and if it's got variable intakes they'll give it a
2.2 or a 2.35. Those seem to be the magic criteria but I doubt
they're based on anything but numbers pulled out of somebody's
backside.

On Sun, 30 Nov 2003 03:13:36 GMT, Scott Ferrin
wrote:


I think it has more to do with the government/military original
specifications, I would think it goes something like this..

Military "We'd like a M2.5 aircraft..."

Manufacturer "Ah but they would require a variable inlet more
development work and thats more expensive!!"

Military "so how fast can you go without all the extra expence?"

Manufacturer " about M2.0"

Military " Ok close enough"

These figures are then carried through the life of the program, even
when those figures are exceeded by a large margin..


cheers



A/C top speeds are illusory ... sometimes I think they're based more on what
comes from marketing than engineering. The F-14 was attributed with 2.34
(it attained 2.41 ONCE in flight test and was artificially limited to 1.88
in the fleet ... though it got there easily enough). The F-18 has a 1.8
claim ... I know NO ONE who's seen close to that (so maybe once in flight
test?).


Sometimes I wonder if the marketing guys just go something like "well
it's got a thrust to weight of X, it's got them there fixed intakes so
it's automatically less than two, and it's not quite as streamlined as
an F-16, let's slap '1.8' on it and call it good".

Any 4th generation aircraft with fixed intakes is automatically
assigned 2 or less and if it's got variable intakes they'll give it a
2.2 or a 2.35. Those seem to be the magic criteria but I doubt
they're based on anything but numbers pulled out of somebody's
backside.

John Cook

Any spelling mistakes/grammatic errors are there purely to annoy. All
opinions are mine, not TAFE's however much they beg me for them.

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