Rocket powered vertical launch sled? Air start?

[ChrisLentz]

Launch pad that has its own propulsion system to kick the rocket off the pad at a stable velocity, then air start the motor at 100-200 feet.Has it been done?I was thinking a competition system that uses 4 rods and an elevator that shoots to the top and stops. Momentum carries the rocket up until the predetermined height for aux ignition.I imagine this could work nicely if constructed strong enough. I suppose you could use pneumatic pressure to launch the sled as well.Comments?

 

[BuiltFromTrash]

Do you mean a piston launcher? Or do you mean a launcher like what the military uses?

 

[ChrisLentz]

Elaborated a bit.

The rocket sits snug on the pad. All set for air start at 200 feet. There are no lugs, it just sits nice in a cradle of sorts.

Press the launch button and bam! all four G80Ts light up under the pad shooting said cradle blasting off to the top of the launch system.

When the cradle reaches the top of the system, it stops and the rocket keeps going. Fast enough for stable flight.

At 200 feet, the main motor kicks in and blasts it even faster/higher.

not the proper use of motors I get it, which is why I thought pneumatic pressure to propel the sled upwards to the top of the rails.

Like circus acrobats on a see saw.

 

[DAllen]

Erm...This sounds bizarre. Is there a specific objective you hope to achieve or is this "I wanna do it cause it's cool" thing?

My first impression is why not just make a 2 stage rocket instead which will have the same (sort of?) result but easier to execute. Otherwise, I think trying to keep the pad pointed upward is going to be a but of an issue...

 

[Handeman]

I think it would be a cool machine, but kind of like a Rube Goldberg thing. Very complicated and prone to bad outcomes in relation to any benefit.

But, if you build it, they will come!

 

[Nytrunner]

A STEM highschool IREC team built a system that used 2 I motors to accelerate their liquid rocket to a stable speed (lower thrust from the liquid engine).
They ended up aborting during countdown though

This is sounds like your idea upscaled.