F-104 maxed out

http://www.f-16.net/reference/versions/f16_79.html

I've read that the F-104's speed is really limited by the
compressor inlet temperature on the J79, and that the
airframe itself supports much higher speeds. Since the
J79 fits (modified) in a F-16, what then if we were to
fit a GE-F110 type engine with closer to twice the thrust?



Regards...

"Bjørnar Bolsøy" wrote in
:


http://www.f-16.net/reference/versions/f16_79.html

I've read that the F-104's speed is really limited by the
compressor inlet temperature on the J79, and that the
airframe itself supports much higher speeds. Since the
J79 fits (modified) in a F-16, what then if we were to
fit a GE-F110 type engine with closer to twice the thrust?



Regards...




What's the point? It's still not going to handle all that well,perhaps
worse with the extra speed. And probably not worth the money spent on the
project.

BTW,would the F-104's inlets then become the major restriction for airflow
into the engine? I believe the jets that use the newer engines have much
larger inlets.

--
Jim Yanik
jyanik-at-kua.net

In article ,
Jim Yanik wrote:

"Bjørnar Bolsøy" wrote in
:


http://www.f-16.net/reference/versions/f16_79.html

I've read that the F-104's speed is really limited by the
compressor inlet temperature on the J79, and that the
airframe itself supports much higher speeds. Since the
J79 fits (modified) in a F-16, what then if we were to
fit a GE-F110 type engine with closer to twice the thrust?



Regards...




What's the point? It's still not going to handle all that well,perhaps
worse with the extra speed. And probably not worth the money spent on the
project.

BTW,would the F-104's inlets then become the major restriction for airflow
into the engine? I believe the jets that use the newer engines have much
larger inlets.

The speed limitation due to the (fixed geometry) inlets arises from the
fact that, going too fast, the inlet will swallow the shockwave,
resulting in compressor stall and other engine misbehavior.

Relatively easy to fit a smaller diameter engine into the space in which a
larger one fit. The retrofit of the 110 engine into the F-14's engine bays
(TF-30's somewhat physically larger than a J-79 BTW) was a real squeeze.

Compressor inlet temp can be handled by water injection (Skyburner F-4 had
it, Greenameyer's F-104 was getting it). Canopy overheating is another
problem.

R / John

"Bjørnar Bolsøy" wrote in message
...

http://www.f-16.net/reference/versions/f16_79.html

I've read that the F-104's speed is really limited by the
compressor inlet temperature on the J79, and that the
airframe itself supports much higher speeds. Since the
J79 fits (modified) in a F-16, what then if we were to
fit a GE-F110 type engine with closer to twice the thrust?



Regards...

Jim Yanik wrote in
:

"Bjørnar Bolsøy" wrote in
:


http://www.f-16.net/reference/versions/f16_79.html

I've read that the F-104's speed is really limited by the
compressor inlet temperature on the J79, and that the
airframe itself supports much higher speeds. Since the
J79 fits (modified) in a F-16, what then if we were to
fit a GE-F110 type engine with closer to twice the thrust?



Regards...




What's the point?

Apart from the shear fun? :^) Acceleration, climbrate, fuel
economy.


It's still not going to handle all that
well,perhaps worse with the extra speed. And probably not worth
the money spent on the project.

BTW,would the F-104's inlets then become the major restriction
for airflow into the engine? I believe the jets that use the
newer engines have much larger inlets.

http://www.dcr.net/~stickmak/JOHT/joht12f-104.htm

"Early Starfighters could not exceed Mach 2.2 without
damaging the engine; on later models with the -19 engine
this was increased to Mach 2.3. The canopy limit is
around Mach 2.6. The airframe on late models is stable
out to Mach 2.8."


Don't know if this can be verified, but I guess a F110 would
be a tight squeeze anyway, having a larger diameter than the j79.



Regards...

Orval Fairbairn wrote in message .. .
In article ,
Jim Yanik wrote:

"Bjørnar Bolsøy" wrote in
:


http://www.f-16.net/reference/versions/f16_79.html

I've read that the F-104's speed is really limited by the
compressor inlet temperature on the J79, and that the
airframe itself supports much higher speeds. Since the
J79 fits (modified) in a F-16, what then if we were to
fit a GE-F110 type engine with closer to twice the thrust?



Regards...




What's the point? It's still not going to handle all that well,perhaps
worse with the extra speed. And probably not worth the money spent on the
project.

BTW,would the F-104's inlets then become the major restriction for airflow
into the engine? I believe the jets that use the newer engines have much
larger inlets.

The speed limitation due to the (fixed geometry) inlets arises from the
fact that, going too fast, the inlet will swallow the shockwave,
resulting in compressor stall and other engine misbehavior.

While it is fesible, and it is a possibility to modify the
inlets...you would get to the point where you have to ask yourself "it
is worth it, or is it cheaper to design a new aircraft".

On Tue, 10 Feb 2004 06:36:25 -0600, "John Carrier"
wrote:

Relatively easy to fit a smaller diameter engine into the space in which a
larger one fit. The retrofit of the 110 engine into the F-14's engine bays
(TF-30's somewhat physically larger than a J-79 BTW) was a real squeeze.

Compressor inlet temp can be handled by water injection (Skyburner F-4 had
it, Greenameyer's F-104 was getting it). Canopy overheating is another
problem.

R / John

If you have access to AW&ST you might want to read about Rascal that
DARPA is kicking around. It's pretty interesting and it's along
similar lines.

"Scott Ferrin" wrote in message
...
On Tue, 10 Feb 2004 06:36:25 -0600, "John Carrier"
wrote:

Relatively easy to fit a smaller diameter engine into the space in which
a
larger one fit. The retrofit of the 110 engine into the F-14's engine
bays
(TF-30's somewhat physically larger than a J-79 BTW) was a real squeeze.

Compressor inlet temp can be handled by water injection (Skyburner F-4
had
it, Greenameyer's F-104 was getting it). Canopy overheating is another
problem.

R / John

If you have access to AW&ST you might want to read about Rascal that
DARPA is kicking around. It's pretty interesting and it's along
similar lines.

Can you be more specific? I searched AvWeek's site for DARPA and Rascal and
came up empty.

"Paul F Austin" wrote in
:
"Scott Ferrin" wrote in message
...
On Tue, 10 Feb 2004 06:36:25 -0600, "John Carrier"
wrote:

Compressor inlet temp can be handled by water injection
(Skyburner F-4
had
it, Greenameyer's F-104 was getting it). Canopy overheating
is another problem.

R / John

If you have access to AW&ST you might want to read about Rascal
that DARPA is kicking around. It's pretty interesting and it's
along similar lines.

Can you be more specific? I searched AvWeek's site for DARPA and
Rascal and came up empty.

You're Googled! :^)

http://www.google.com/search?hl=en&l...UTF-8&oe=UTF-8
&q=DARPA+Rascal


Regards...

There are three redlines for the F104A with either the -3b or the -19
engine.
710 KIAS, 121C or M 2.0. I believe most Zipper pilots honored these
limits in the breach, as the Limeys say. They are all artificial
limits as even the -3b engined proverbial 'squadron dog' would exceed
all 3 limits. The hard concrete limit is the aluminum airframe. M 2.4
at STP will anneal the aluminum alloy and now the design strength is
gone never to return. (The F106 on display at the USAFA is a case in
int - 2.46 Mach and she was grounded forever.)
FWIW the 2.0 limit is because of reduction in lateral stability beow
USAF criteria; Cnbeta limit is .03; think of this as a stability
restitution coefficient. Of course if you don't do anything really
dumb like stomping on teh rudder - hey,let 'er rip.
The KIAS limit is because of internal pressure limits at the rear of
the compressor. There is a limit built into the fuel control and it's
quite noticeable when it cuts in - but you're over 710 when it does.
the airplane is accelerating like mad because those little scoops are
really taking in the ram air and all of a sudden the 'governor' cuts
in and she stops accelerating. I remember seeing at that point about
750 and 1.2 on the clock at about 100 ASL just before I went right
over the top of a shrimp trawler on a test hop early one Florida
morning - and that was with an old tired -3b engine.
The 121C limit is from a temp sensor in the generator cooling air
duct. It turns on the Slow light. The 100 CIT is from the T2 probe at
the front of the compressor.
I know a couple fearless single Zipper pilots who have been out all
the way up at altitude; neither would own up to what their Mach was.
One of them returned with scorched paint on his warhead-loaded AIM9s.
The other was turned ;ate on a supersonic target on a night exercise -
the conroller called 'skip it - we're too far behind.' Howie replied
'keep talking' and put teh throttle in teh far left corner. He heard
the controller over an open mike call otu to his buddies - 'Hey! Come
look at this!' Howie caught and passed an f4 cruisng supersonic in
(probably) minimum AB. Howie, back then, wasn't about to let a little
thing like a book limit bother him. He also let teh F4 know he was
there. We wondered what the F4 crew thought as something blitzed past
them close aboard at least 500 knots faster than they were cruising.
One thing I noticed was the fuel flow increase as the IAS increased. A
static 8500PPH at the end of the runway (those little intakes!) during
the pre-takeoff runup rose to about 12500 at 600KIAS, still on the
deck. Since the fuel-air ratio is fixed that indicates the thrust
developed increased proportionately. Once took a Dash19 Zipper right
off the line, usual war load of 20mm ammo plus 2 AIM9Bs, from brake
release to 45000 in 90 seconds flat. Takeoff acceleration was from
brake release to .97 - 43 seconds. Rotated to hold .97 and at 40000
stood her on her tail. Exhilirating ride! Mommy, I want a Zipper for
Christmas!
Walt BJ