Ascent profiles (was Re: Ranger 7, Atlas LV-3A, Agena B 1.0 released.)

[Roger Burton West <roger@xxxxxxxxxxxxx>]

On Mon, Mar 25, 2002 at 09:41:40PM +0200, ??? ????? wrote:
>Hi there
>
>I've just found out about this great sim, very well done. 
>
>Now since flying rockets is not up my ally, can someone give me some instructions? I've read the manual. It seems easy enough to launch the craft, but the manual says that the pitch should be changed upon reaching certain highet, is there a rule of thumb so to speak? or is it a calculated approach?

Martin has asked for suggestions (on the web boards) regarding an
ascent-profile instrument for possible inclusion in a future version of
Orbiter.

In the short term, though, the rules of thumb which are working for me
are:

- start at 70 degrees above the horizon;
- drop 10 degrees for every 40-50 km altitude;
- have the Orbit MFD running; the grey line is the minimum safe orbital
radius;
- once your radius gets above that, pitch down sharply (often 20 degrees
or so) to keep your apoapsis distance as constant as possible while you
accelerate to orbital speed.

I know this isn't as efficient as it might be - or I wouldn't need to
pitch down - but with a forgiving craft (shuttleA, shuttlePB, glider)
it's not a problem.

Roger