In article ,
Guy Alcala writes:
Peter Stickney wrote:

In article ,
"John Carrier" writes:
Did the Zipper C model get the higher output J-79? I'm sure the A was
lighter and cleaner. Any less stable w/o the ventral fin? The F-8 ventrals
were installed to improve supersonic stability, the A's and B's were a
little squirrely in the 1.5 range or so. Even the C/K would do a slow dutch
roll @ high mach if the yaw stab was not up to spec.

R / John

R / John
"WaltBJ" wrote in message
om...
Bunch of kids. 22 Jan 1931, Ketchikan, Alaska. USAF Aviation Cadet
Class 54-H, 28 Apr 54. F86F Sabrejet, F86Dog, F102, F104A, F4, 2000+.
Last flight in F4 Jan 31 80. Hung it up for good 31 March 80. Carter
wore me out. 104A with the J79-19 engine - yahoo! .9 to 2.0. 27 miles.
1'45", 1000 pounds of fuel....
Walt BJ



Walt flew the Hot Rod Model A's - an early air-to-air only F-104A with
the original small-0bore -3 engine replaced with the -19 engine used
on teh F-4E.

A 'big' J79 anyway, but not the -17 used in the F-4E, albeit the same thrust. The
-19 was the one also used in the F-104S (as you know). I don't know what the
differences were between the two engine subtypes, but assume it was accessory
locations and the like.

According to my files, teh biggest difference was a differenct control
fir the Afterburner fuel pump, that allowed a continuously variable
fuel flow from Min-AB to Max-AB. (That's not a trivial thing - you've
got to have soem amount of variable delivery to deal with the change
in mass flow qith altitude and airspeed, then throw in some other
"logic" (Cams & fueldraulic analog computer, in this case) to nudge
all that around to match the throttle commands.)

To further answer John's question, the F-104A came with
various versions of the J79-3, before some of them were retrofitted with the -19.
The F-104C had the J79-7 with about 1,000 lb. more thrust in A/B than the -3,
essentially the same thrust as the -11 in F-104Gs.

They literally had about a Metric Ton more push than the
C model (I know, I know, I'm mixing units here, but I'm waxing
hyperbolic here), and performance that the documents I have on it,
and computations I've done have to be seen to be believed.
According to my quick reference (F-104A (-10 Engine) SAC Chart, June
1970)

Typo for '-19', presumably.

Oh, yes. definitely.

The upper right corner of teh envelope is Mach 2+/67,000'. The whole
envelope ios bordered by either Q or airfrae heat limits - it never
runs out of power. During a Point Intercept mission,it would be
passing 30Kft in less than a minute after breaking ground.
(Oh, yeah - since it could fly so high, it would go just as far at
Mach 2 as it would a Mach 0.9)
I'm in awe of the beast.

The performance section of the -1 (equivalent to the-1-1) for the a/c is quite
impressive. I've got the F-104A-D -1 dated 1 June1968, which covers various
versions of the a/c with -3B, -7, and -19 engines. The -3B is pretty hot,
although there's a bit of transonic acceleration sag (we're talking relative to
the later versions here) up to about M1.4, then it really starts to cook. the C
w/-7 is better, but the A w/-19 is just awesome. I've been told by someone with
access to -1s for both, who's also talked to pilots who've flown them, that even
the heavier F-104S can give an F-15 a run for its money in climb and acceleration,
and it actually has a greater supersonic point intercept radius (easy to believe
with a turbojet instead of turbofan). Naturally, the F-15 wins hands down on
avionics and weapon load, and it can fight at speeds below 450 KIAS.

That sounds about right. Of course, when you start hanging
Sparrow/Apsiede sized missiles on an F-104, you really start piling up
drag But Fast. A Back of the Envelope quickie goxes a Drag Index for
an AIM-7 on an F-104 to be about 6, (Drag Index is DeltaCD * 10000, of
1 Drag COunt = 0.0001 Cd) It adds up fast.


The biggest problem I see with the F-104A and to some extent the F-104C is the
relatively low G limits when carrying anything more than 1,000 lb. of internal
fuel -- It's typically in the 5-5.6G range. However, that's also about the buffet
boundary for guns tracking at combat speeds, and I imagine it was widely ignored
(as were the Q limits) when necessary. I know of one pilot who had an F-104D
model up to 850KCAS (Q limit is 750) at 5,000 ft. MSL in level flight, with a USAF
general in the back seat, and he mentioned to the general that they were almost
certainly faster than the official low altitude world speed record (held by the
Project Sageburner F-4) at the time. I wonder if the G and S had higher g limits

I don't know offhand. To tell you the truth, I really don't think
that it makes much difference in Real Life - you're limited by Buffet
at low speeds (And of course, with a T-Tail, the runaway pitchup.
Definitely Nature's Way of sayig you've pulled enough G) and at high
speeds by Gavailable. Most supersonic types lose pitch effectiveness
at high speeds - they just can't pull that many Gs anyway, The F-104
was different - apparently it just didn't care, and at high speeeds,
it had lift to burn.

Hopefully Walt Bjorneby will show up and correct light on our musings
with the torch of experience.

- I know the G was strengthened for prolonged flight at high Q for the strike
role, and the S was based on it.

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster