Mark,
Yes that works, if you are looking at parasitic drag only. But at the
time of the pullup induced drag is highest. Most likely you will lose that
5mph gain. Also parasitic drag is higher (faster = more drag).
But you are right, except for sidearm guys no one can throw vertically
with even 1/2 the speed of horizontal. But in theory the vertical launch
should win.
Jason
----- Original Message -----
From: "Mark Drela" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, August 10, 2000 5:48 PM
Subject: Re: [RCSE] How should an HLG launch?
> >So we look at the situations:
> >
> >launch 1 is level. The plane starts out level and then
> >commenses a hard high G pitch up to climb speed.
> >Probably 10-30% of the throw speed is turned to drag!
> >
> >launch 2 is at a 75 degree angle. The plane is thrown
> >at the same speed and no drag is created pitching up
> >the correct climb angle.
> >
> >Launch 2 wins.
>
> Not necessarily. As an example assume a 5 mph wind...
>
> Launch 1 is thrown near-level at 50 mph, so airspeed is 55 mph.
> WHen plane rotates vertically (neglect induced drag for now),
> its vertical velocity is 55 mph.
>
> Launch 2 is thrown near-vertically at 50 mph (ouch!).
>
>
> Launch 1 has about 10% more speed and therefore
> 20% more energy at the start. The pullup will
> bleed off some of this initial advantage, but
> not all of it. I estimate that about 5%-10%
> of the initial energy is lost in the pullup
> maneuver, so Launch 1 goes about 15%-10% higher.
>
>
> In reality Launch 1 allows a run-up and a harder throw,
> so its advantage is greater, even if there's no wind.
>
>
> --
> - Mark Drela
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