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by pieterbreed 6296 days ago
Well, I don't have any material on it but you can see that it makes sense from a mechanical physics point of view. Load up a craft to maximum possible weight (with ballast even) Then fly as high and is fast as you can (during which you build up the maximum achievable potential and kinetic energy) then during a dive build up as much speed as you can (during which you convert your potential energy from the weight and height of the craft into more kinetic energy) as you level out, you dump the excess weight and start climbing. Since you now have less weight but the same kinetic energy, you are free to take your craft higher than the height from which it started to descend.
1 comments

Yes, your explanation makes sense. That's what I thought. Nonetheless, I was interested in more in-depth technical info... some technical papers / reports on it would be interesting. By the way, have you heard of the pop-up maneuver?
no! please elaborate! :)
The pop-up maneuver's goal is to minimize exposure to enemy fire. Imagine that you're flying an F-16 over enemy territory and that you want to hit a nuclear power-plant with a couple of JDAM's. Since the target is certainly protected by lots of AAA and SAM's, you want to drop the bombs as far away as possible from the target. In other words, you definitely do not want to fly over the target, as that will most likely get you shot down.

You can use the pop-up maneuver then. You fly low and fast to avoid radar detection and AAA fire. When you get close to the target you climb at 45 degrees, roll 180 degrees (you are now flying inverted), prepare the JDAM's to be deployed. You then pitch up and when you are at the top of a parabolic flight path, you release the JDAM's. The inertia build-up during the ascent will make the bombs go faster and farther. Once the bombs are deployed, you fly low again.

There are some technical papers on this. It's heavy math: optimizing flight paths is not exactly a trivial problem ;-)

This sounds very much like something the SA Air Force did with their mirages in the Bush war of the 70's and 80's.

BTW - There is a book written about the history of the Mirage in the SAAF called 'vlamgat' (lit. fire/fiery - behind/ass). Try http://www.saairforce.co.za/reviews/33/vlamgat-cd.

Anyway. In this book, which is written by an ex-pilot, a maneuver is described which sounds very similar to the pop-up. The aircraft also approaches the target at low altitude, then pitches up. As the pilots pull up on the stick they release their bombs, but continue climbing up and away. The bombs (old fashioned, dumb bombs) would then fly in a parabolic trajectory like you'd expect and land somewhere near the target ;)

If I remember correctly this tactic was actually used in combat with surprisingly effective results. I say surprising because nobody believed you could actually hit a target with a bomb that flies in a trajectory with a horizontal length of a few 100 to 1000 meters and was released on the pilot's 'gut' feeling...