Have i missed something?

[HondaShadow600]

Out of curiosity, will the TF-30 have that extra thrust at sea level?

[Spurts]

Sorry, no M2.5 Tomcat this time ;)

 

I'm pretty sure IM said the TF-30 will have more thrust than the F110 once above 1.6M based on historical data, so if I can drag the B to 2.15M then 2.5M in the A might still be doable. Stories of "It wasn't me, and I won't say who it was, but someone took an A to 2.7M at 70,000ft" exist. And yes, I know flight above 50,000 without a pressure suit is not allowed, but that is likely why no names were given.

[Quid]

Out of curiosity, will the TF-30 have that extra thrust at sea level?

 

Not sure what you mean/are expecting? Engine thrust is highly dynamic; it's been discussed a number of times on these forums, but to put it far too simplistically, as speed increases, thrust increases, as altitude increases, thrust decreases. The result can be shown as a power curve at a given altitude. The Tomcat has a variable inlet, so at lower altitudes it actually starts losing thrust for a bit as the jet goes from high transonic to supersonic and the ramps deploy to full (smaller inlet area), before thrust starts increasing again. The difference between the TF-30 and the F110 is that the F110's computers start ebbing the thrust off as the jet gets to very high speeds (esp >1.6M), while the TF-30 just keeps producing more, so at high speed and high altitude, the TF-30 eventually starts outputting higher thrust than the F110.

 

I'm pretty sure IM said the TF-30 will have more thrust than the F110 once above 1.6M based on historical data, so if I can drag the B to 2.15M then 2.5M in the A might still be doable. Stories of "It wasn't me, and I won't say who it was, but someone took an A to 2.7M at 70,000ft" exist. And yes, I know flight above 50,000 without a pressure suit is not allowed, but that is likely why no names were given.

 

Drop down to about 35,500 and you'll get 2.35 out of the B if it's clean.

[Spurts]

Drop down to about 35,500 and you'll get 2.35 out of the B if it's clean.

 

"Clean", can't get rid of the pylons. I tend to do my speed runs at or above 50,000ft to save on fuel. I have had the B to 2.15@50,000 and 2.05@52,000 with a "Clean" aircraft.

[eatthis]

"Clean", can't get rid of the pylons. I tend to do my speed runs at or above 50,000ft to save on fuel. I have had the B to 2.15@50,000 and 2.05@52,000 with a "Clean" aircraft.

 

you can get rid of pylons in rearm menu, also i think best altitude for mx speed is 35k. not 100% on that 1 though

[Spurts]

i think best altitude for mx speed is 35k. not 100% on that 1 though

 

generally 36,000+- for max speed. I was more aiming for a 275nm run for minimum time, and 36,000 would have run me out of gas real fast.

[eatthis]

generally 36,000+- for max speed. I was more aiming for a 275nm run for minimum time, and 36,000 would have run me out of gas real fast.

 

not sure why, thats the cruise altitude so surely thats the best fuel/speed ratio??

itl use less fuel higher because theres less air (so less fuel needed for the same a/f ratio) but the power will drop off for the same reason

[Spurts]

That isn't necessarily the best cruise alt. In the Tom true best cruise is usually 30-32 at 0.74M when loaded. This is dictated by the wing sweep. Best cruise is when you get cruise AoA at the max speed before the wing starts really creeping back. If you go too high or too fast you increase the lift-induced drag as you either have to increase AoA beyond L/D max or the wings sweep back. Now, you can zip around at 0.9M and 36,000-40,000ft loaded and still outrange a Hornet, but 32k and 0.74M you will just sip fuel. Slowing down even more to around 0.65M, and dropping alt a bit, and you can stay airborne "forever". I've seen under 2,000pph per motor.

[eatthis]

That isn't necessarily the best cruise alt. In the Tom true best cruise is usually 30-32 at 0.74M when loaded. This is dictated by the wing sweep. Best cruise is when you get cruise AoA at the max speed before the wing starts really creeping back. If you go too high or too fast you increase the lift-induced drag as you either have to increase AoA beyond L/D max or the wings sweep back. Now, you can zip around at 0.9M and 36,000-40,000ft loaded and still outrange a Hornet, but 32k and 0.74M you will just sip fuel. Slowing down even more to around 0.65M, and dropping alt a bit, and you can stay airborne "forever". I've seen under 2,000pph per motor.

 

i tested it loaded in 1k foot increments from 30-40k at mach 0.72. 35k was the sweetspot for fuel usage in them test conditions

ps with no stores and little fuel you can EASILY cruiser at 1500pph per motor at 35k

[captain_dalan]

you can get rid of pylons in rearm menu, also i think best altitude for mx speed is 35k. not 100% on that 1 though

 

generally 36,000+- for max speed. I was more aiming for a 275nm run for minimum time, and 36,000 would have run me out of gas real fast.

 

not sure why, thats the cruise altitude so surely thats the best fuel/speed ratio??

itl use less fuel higher because theres less air (so less fuel needed for the same a/f ratio) but the power will drop off for the same reason

Not sure why (probably an engine thingy), but the manuals confirm it, 35-37000, best dash altitude.

[Spurts]

i tested it loaded in 1k foot increments from 30-40k at mach 0.72. 35k was the sweetspot for fuel usage in them test conditions

ps with no stores and little fuel you can EASILY cruiser at 1500pph per motor at 35k

 

Ah, yeah the manual says 50,000lb best cruise is a bit north of 41,000ft. at 70,000lb it shows around 34,000ft. 0.720-.0730M depending on stores.

 

Not sure why (probably an engine thingy), but the manuals confirm it, 35-37000, best dash altitude.

It's an engine thing. You will find that to be true in everything from the F-4 to the F-15

[HondaShadow600]

Not sure what you mean/are expecting? Engine thrust is highly dynamic; it's been discussed a number of times on these forums, but to put it far too simplistically, as speed increases, thrust increases, as altitude increases, thrust decreases. The result can be shown as a power curve at a given altitude. The Tomcat has a variable inlet, so at lower altitudes it actually starts losing thrust for a bit as the jet goes from high transonic to supersonic and the ramps deploy to full (smaller inlet area), before thrust starts increasing again. The difference between the TF-30 and the F110 is that the F110's computers start ebbing the thrust off as the jet gets to very high speeds (esp >1.6M), while the TF-30 just keeps producing more, so at high speed and high altitude, the TF-30 eventually starts outputting higher thrust than the F110.

 

 

 

 

You've basically answered my question. I was asking if the TF-30 will put out more thrust at lower altitudes because of the ram air effect that Okie mentioned for example. I believe he said that the engine was able to put out about 28,000 pounds or so.

 

 

Now what I didn't know is that the F110's computers actually started cutting some of the thrust once the jet reached higher speeds. While the F110 is an objectively better engine. I find it quite fascinating to learn new things about the TF-30

Edited October 11, 2020 by HondaShadow600