Posted by dlevine2100 on
URL: https://www.shado-forum.com/Interceptors-tp1500519p1500583.html

--- In [hidden email], "David Richards" <davrich@b...> wrote:
>Explanation for no visible flame as applied to interceptors and
Apollo Lunar>Modules is that although combustion takes place - this
takes place
inside
>the engine - once the gases exit the engine - there is no oxygen to
sustain
>combustion and therefore no flames will be or can be seen as they are
effectively snuffed out on exit the confines of the engine nozzles.
I don't agree with this. You can see the "flame" of the space shuttle
engines all the way until they are shut off (burning hydrogen with
oxygen). On the other hand, with the Apollo Lunar modules, they used
hypergolic propellants, hydrazine and something else. You probably
could had seen the "flame" if you had been just underneath the
nozzle. Actually, you can see a small flame when the reaction control
system (small thrusters to control attitude) fires.

> Flaming exhausts are primitive technology - the Interceptors must
use a form
> of ion drive - charged particles that provide the thrust - hence no
visible
> exhaust - just dust getting blown around.
I don't remember the physics of ion propulsion, but my guess is that
you would need much bigger ion engines than what the interceptors
show to produce enough thrust like what they show when the
interceptors take off.

I think the main issue is that they just modeled the interceptors
having in mind that they were like combat aircraft, but with some
changes because they would be in space. Near the missile, they have
something that looks like air intakes. It is also interesting to see
that they have skids, like if they could land horizontally... I don't
think these could be of much use on the moon!

David Levine