Streak Eagle- Time to Climb

Jaybird180

Jaybird180

Final Approach
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Jaybird180
In this video to set the time to. Limb world altitude records in 1975, they used Immelmann to climb and a 4-6g pull to continue the climb after accelerating.

Why did they do this? Why was this better than a simple Vy climb at whatever AoA was calculated to yield best results?

I understand the F15 has greater than 1:1 thrust-weight ratio and it could have something to do with it. Just hoping than someone could explain why the high G maneuvering wouldn't be wasteful of energy when trying to set the record.

Pt1

Pt2
 
Donno but did you notice the nose gear retracting before the mains were off the ground?
 
Missed that. In a video I have on VHS discussing the flight, the Streak Eagle was left untainted for weight and only that badge was applied. I imagine they probably considered landing dead stick after reaching target altitude.
 
Perhaps it needs so much speed to keep those engines fed w enough air for max thrust?
 
Jaybird180 said:
Missed that. In a video I have on VHS discussing the flight, the Streak Eagle was left untainted for weight and only that badge was applied. I imagine they probably considered landing dead stick after reaching target altitude.
Click to expand...

Can't land an Eagle dead stick, you run out of gas - you punch. Not too many things that will make you punch but that is def on the short list. The -1 says that you could have enough hydraulic pressure to move flight controls if you keep the engines windmilling above 12%. Problem is that they'll drop below that before you get in the flare.
 
Really enjoyed watching these videos, thanks. Amazing performance. Loved the climb profiles, I would have never imagined them using an Immelmann like that to accelerate and then continue the climb! Awesome!
 
EvilEagle said:
Can't land an Eagle dead stick, you run out of gas - you punch. Not too many things that will make you punch but that is def on the short list. The -1 says that you could have enough hydraulic pressure to move flight controls if you keep the engines windmilling above 12%. Problem is that they'll drop below that before you get in the flare.
Click to expand...

Very interesting...and I hoped you'd chime in too.

I saw a vid of an F16 landing dead stick. They have an engine that burns hydrazine for hydraulic and avionics power. Interesting that a dual engine out on a combat aircraft would mean the pilot must jettison the aircraft. Did they not think about air-ground? Was this remedied in the Strike Eagle?
 
Jaybird180 said:
Very interesting...and I hoped you'd chime in too.

I saw a vid of an F16 landing dead stick. They have an engine that burns hydrazine for hydraulic and avionics power. Interesting that a dual engine out on a combat aircraft would mean the pilot must jettison the aircraft. Did they not think about air-ground? Was this remedied in the Strike Eagle?
Click to expand...

15 has a spare engine:wink2:
 
Jaybird180 said:
Very interesting...and I hoped you'd chime in too.

I saw a vid of an F16 landing dead stick. They have an engine that burns hydrazine for hydraulic and avionics power. Interesting that a dual engine out on a combat aircraft would mean the pilot must jettison the aircraft. Did they not think about air-ground? Was this remedied in the Strike Eagle?
Click to expand...

Nothing to remedy! Combat proven for over 30 years. Two engines with triple redundant systems are good enough for us. Hydrazine is NASTY, NASTY stuff and causes a LOT of problems with handling/storing/EP procedures, etc. I have heard of 3 dual engine losses in the history of the Eagle. I've been flying it for over 10 years and have heard most of the stories that have cost us aircraft over the years. There's just not that much concern for dual engine failure - thats whats so great about having two motors!
 
Same for the Hornet, in a similar vein. Guy took an SA-7 up the tailpipe in GW1 and flew home with 0 oil pressure for over half an hour. Notably, the NATOPS manual now notes that our motors can run for 1/2 an hour without oil pressure......little bennie from that bad day :) Dual engine failures are especially uncommon, like the Eagle, and we don't waste weight with a bunch of extra redundancy beyond dual motors, dual hyds, dual FCC's, and 4 channel digital FBW (with mostly dual servos for every flight control surface). There is a backup mechanical link to the stabilators in the event of a catastrophic failure of the FCS or total loss of electricity, but without hyds (and generally by default without one good motor), that no workie. Same same for windmilling to keep the hyd pumps turning, but all that really buys you in a dual flamout is time to attempt a re-start, and get the jet into a reasonable ejection envelope if it doesn't work.
 
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