Mark,
I think if you do the "math" a launch that places the plane in exactly
the correct climb angle (say 75-90 degrees up) that will be the best launch.
Why? Well if you assume some things then the turn is the high drag
component. So assume the following:
- launch speed is constant
- wind is constant at all altitudes
- launch climb is same in both cases.
So we look at the situations:
launch one 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.
In reality though, throwing the plane vertically is harder than throwing
it up. The wrist and arm speed is lower, and in the end a hard throw level
followed by a hard pitch vertical is the best.
Jason Werner
----- Original Message -----
From: "Mark Drela" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Thursday, August 10, 2000 2:13 PM
Subject: Re: [RCSE] How should an HLG launch?
> Dick Barker writes:
>
> >The most efficient climb angle is almost straight up.
> >Seventy five or so degrees is about right as anything
> >greater will drift behind you on the way up and make
> >it hard to get a good transition at the top. The steeper
> >it goes, the less drag is induced by the coef of lift.
>
> This might be misinterpreted.
>
> I think you meant to say that the _launch_ should be
> almost level, and the _climbout_ after that very steep.
> This will extract maximum additional energy from the
> wind. A near-vertical launch does not benefit from
> the wind at all.
>
>
> --
> - Mark Drela
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