F-104 E-M diagrams?

[Temetre]

vor 3 Stunden schrieb ChrisKermit:

Don’t get me wrong, I absolutely believe that you are approaching that matter neutrally. I just find it quite interesting by how much even “official” documents differ sometimes in their data. 

Looking forward to that! The F104 and F4 are both equally exciting IMHO!

You could even say the F-104 was a bit too exciting  

[Smyth]

21 hours ago, ChrisKermit said:

How would you judge the 104s vertical capabilities vs the other fighters?

Highly.

I don't have any sophisticated metric for this (altitude gained in a spiral, or speed gained/lost in a loop), because those require a full lift/drag/thrust model to calculate. However I do have some official numbers for raw subsonic 1G climb potential.

From the 1958 F104C Standard Aircraft Characteristics (declassified).

At 1000m=3821 ft we get 47100ft/min = 240m/s at 19201lb which is almost full internal fuel.

Now to compare some other aircraft:

• F-4E (with slats) from FTC-TR-72-35 -> 39112ft/s at 41185lb (57%) fuel
• Mig-23ML (45 or 72 wing sweep) from "Practical Aerodynamics of Mig-23ML" ->215m/s = 42300ft/s at 12100kg (28% fuel)

And for even more laughs:

• F-14A from its 1977 Standard Aircraft Characteristics -> 42368ft/s at 53166lb (60% fuel)

This gives an idea, but the fuel states used by 50s US, 70s US, and USSR are very different. To guesstimate a more fair comparison, I'll use the fact that Climb Potential = Specific Excess Power, so we can multiply by the reference weight and divide by a slightly different weight to estimate climb potential at a different fuel state. This assumes no change in excess power due to induced drag, but the actual change is very small in high speed level flight (few percent) so it is a reasonable simplification (slightly conservative for scaling down the weight of the US fighters, and slightly optimistic for scaling up the weight of Soviet fighters).

After some unit conversion, here are the results for 1000m, 50% useable fuel:

• F104C: 265m/s
• F-14A: 220m/s
• Mig-23ML: 200m/s
• F-4E: 200m/s

These are the highest performing tactical fighters of the mid-70s, and they are all annihilated by a ridiculous lawn dart from 1958. Adding 1000lb for an F104G doesn't change much. It's hilarious really, which is a theme for the F104 and the reason I am so excited for it.

Edited August 29, 2023 by Smyth

[SuperKermit]

Am 28.8.2023 um 06:03 schrieb VZ_342:

Maybe everyone has got the "dash 1" manual already, but here it is.... (dated 1960)

Quite remarkable btw, that the flight manual of such a complex aircraft only has 226 pages. The manual of a C-182T has almost twice the count!

[Temetre]

vor 3 Stunden schrieb ChrisKermit:

Quite remarkable btw, that the flight manual of such a complex aircraft only has 226 pages. The manual of a C-182T has almost twice the count!

Tbf most of the times theres tons of seperate manuals. Seems to vary quite a bit how complete the 'main' manual is.

[TLTeo]

12 hours ago, Smyth said:

These are the highest performing tactical fighters of the mid-70s, and they are all annihilated by a ridiculous lawn dart from 1958.

I honestly wonder how these numbers compare to a Viper.

[SuperKermit]

vor 14 Stunden schrieb Smyth:

These are the highest performing tactical fighters of the mid-70s, and they are all annihilated by a ridiculous lawn dart from 1958. Adding 1000lb for an F104G doesn't change much. It's hilarious really, which is a theme for the F104 and the reason I am so excited for it.

Absolutely amazing indeed!

Many thanks for the data compilation and clarification, @Smyth! 

I really would love to see a version with the -19 engine as that version brings the concept to the boil: an aerial hot rod

[SuperKermit]

vor 14 Stunden schrieb Smyth:

I don't have any sophisticated metric for this (altitude gained in a spiral, or speed gained/lost in a loop), because those require a full lift/drag/thrust model to calculate.

Well, if one would have all the E-M data something like that diagram on page 13 should be possible. I also like the depiction of the relative performance on page 10 where the color coding shows the relative gain in energy. But for the 104 data we will probably have to wait for the DCS flight model. 

[IvanK]

F104G Sustained G curves Clean Guns only from Lockheed SURE report Lecture 6 Pg 47

 

 

Edited August 30, 2023 by IvanK

[Smyth]

12 hours ago, TLTeo said:

I honestly wonder how these numbers compare to a Viper.

Calculated the same way from SAC pages, low altitude climb of an F16A is 270m/s at 1000m and 50% fuel, so it just edges out the F104C. True 4th gen air superiority fighters like F15C will out-climb the Starfighter comfortably, but not by a huge margin (at low altitude... F104 tiny wings don't like high altitude, so F15 and the like can keep climbing where the F104 can't even go while subsonic).

2 hours ago, IvanK said:

F104G Sustained G curves Clean Guns only from Lockheed SURE report Lecture 6 Pg 47

Yeah, that was my source. All I did was convert to a more familiar format in an attempt to compare to other jets.

[IvanK]

Rummaged through some old paper docs I had stored away. Average quality.

Edited August 31, 2023 by IvanK

[Bremspropeller]

Hey Ivan, thanks for digging those up!

That's precisely the EM diagrams I rememberred. Looks like I rememberred a bit optimistically, though: 6g sustained, not 7g, at the conditions I mentioned in my first post (5000ft, 50% internal fuel, two Sidewinders).

[SuperKermit]

Great documents, Ivan! Thanks for bringing them up!

I wonder whether these numbers include the usage of flaps. Probably not?

[Bremspropeller]

They do. You can see the step in the Ps curves at Mach 0.85, where the flaps are coming up.

[SuperKermit]

I really would like to know how that performance comparison would look like with the F-104S with its additional power!

[Kalasnkova74]

This thread connects the dots on why so many air arms of the Cold War (India, North Vietnam, etc) gave the F-104 a very wide berth. Getting dived on by a Mach 2 death rocket that can counter a defensive break by climbing and killing your subsonic a$$ is not a welcome prospect. A capably flown Starfighter could give an Eagle driver fits , much less some poor schmuck in a MiG-19 or Hawker Hunter. 
 

 

Edited November 21, 2023 by Kalasnkova74

[Tiger-II]

F-104 is a mis-understood aircraft for the simple reason it isn't a turn fighter.

F-104 and F-4...what a time to be alive!

[TLTeo]

I finally managed to find more than just the usual supersonic charts that the F-104G manuals typically come with. The data is for the -3B engine F-104A (so lighter but noticeably less powerful) with two sidewinders, but it tracks with the rest of the info in this thread - depending on weight, at sea level it'll hold ~6G without maneuvering flaps between Mach 0.8 and 0.9, so that works out to ~12 or so deg/s sustained turn rate. There's some caveats between different engines, maneuvering flaps, etc etc, but yeah, not too shabby for a 1950s supersonic aircraft supposedly incapable of turning.

Also, the stick shaker kicking in at Mach 0.6/0.7 is hilarious, it really shows how useful the addition of combat flaps was. Definitely don't try 1 circle fights.

 

Edited February 10 by TLTeo