From: rijrunner@frii.com
Henry Spencer wrote:
> In article <20040212005330.11576.00001803@mb-m12.aol.com>,
> Allen Meece wrote:
>
>><>solved only when Harvey Allen realized that a reentering spacecraft was
>>*NOT* an aircraft and should not be designed like an aircraft.>>
>>
>> Bless Harvey Allen but some would say that the reentry problem has yet to
>>be solved. We invented better thermal insulation and called it a reentry
>>solution but it's an unsatisfactory way of descending from orbit, as we
>>witnessed with Columbia.
>
>
> Some would say that the reentry problem was solved quite satisfactorily,
> until the aircraft nuts got their foot in the door and started insisting
> that spaceships had to look and act like aircraft. The Apollo heatshield
> had tremendous safety margins, and a little bash from falling debris
> wouldn't have bothered it in the slightest (not least because the really
> crucial part of it wasn't exposed during launch).
>
> But ablative heatshields don't work very well if you start insisting that
> the vehicle has to have *wings*. That's what killed Columbia: the long,
> slow, reentry of a winged vehicle gives it a prolonged roasting rather
> than a quick blowtorching, requiring thermal protection that radiates heat
> away rather than soaking it up... and thus needs exotic high-temperature
> materials, which typically involve compromises in areas like physical
> durability.
>
>
>> It's premature to say airplanes can't reenter.
>
>
> Nearly half a century ago, we already understood that an airplane shape
> was not the best choice for reentry.
Faget had an interesting compromise to that by making the
re-entry at high attitude which essentially made the winged
vehicle a capsule for the re-entry. The wings helped reduce the
thermal loading, IIRC.
--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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