Launch of worlds largest model rocket (Saturn V)

[Dr Mordrid]

36 feet tall and 1,600 lbs

YouTube link....

Cool

He needs to take that pup out west to a salt flat and do a multi-stage launch.

THAT, ladies and gentlemen, would be way beyond cool.

[KRSESQ]

Beautiful.

Kevin

[cjolley]

OK NASA, let's see you land one back upright.

[Nowhere]

Sort of...meh.

I guess for me it's not a model of Saturn V at all.

Does it look like Saturn V? Yup.
Is it dynamically similar to Saturn V? Uhmmm...almost couldn't be further from it (perhaps they should think about igniting its engines in sequence, during flight, so to provide just enough force for liftoff...)

Sort of like I wasn't really impressed by aerobatics made with B-52 model posted here some time ago; totally shatters suspension of disbelief.

[Dr Mordrid]

OK NASA, let's see you land one back upright.

VTOL rockets you want 'eh? Well, a NASA test program did it in 1995/

Meet the Delta Clipper -

YouTube video.....

Delta Clipper


NASA canceled it, but the tech is still unded development by Jeff Bezos company Blue Origin as the New Shepard (named after Alan Shepard). It's first flight is in this video, a short hop just to make sure the system worked before it went into a series of very secret tests that continue to this day in various forms -

YouTube video - ground view....

New Shepard - first of a series under very secret testing


and this is a collection of tests by John Carmack's Armadillo Aerospace, mainly tests of their X-Prize Cup Northrop-Grumman Lunar Lander Challenge prototype autonamous lunar lander's guts. Some are successful, some are less so and some are downright silliness like the rocket powered crane truck , but they are dead serious and could be launching people a lot sooner than more publicised outfits.

The path flown by the lander is the N-G/LLC test sequence: up/hover/translate a few hundred meters/hover/land, and do it twice in a couple of hours. Since this video they have done it successfully several times.

YouTube video - mixed.....

X-Prize Cup lunar lander entries


and what's on the slab in the lab - an LEO launcher that goes into testing very soon

[Nowhere]

This configuration seems highly intolerant of single engine failures...

[Dr Mordrid]

Almost all rockets are. No American rocket since the Saturn V has been engine-out tolerant, and it could only lose one engine. For most all others one engine goes out and it's end of mission - at least nothing until SpaceX's Falcon 9. It can lose up to 2 of its 9 first stage engines and still continue to orbit by burning the rest longer and extending the second stage burn. Engine-out was one of its primary design goals, right along with stage reusability (first stage is for sure and they're working hard on a reusable second stage).

[Nowhere]

It's not about completing the mission, it's about safe abort modes. Shuttle can do it, so I'd say it IS engine-out tolerant.

OTOH rocket in this image has a problem with overall layout, it would have to at least shut down one more engine, opposite to the one which fails, to remain stable. And react quickly, not to be ripped apart. And the still...only half of the engines running would give much lower safety margin.

[Dr Mordrid]

It's not about completing the mission, it's about safe abort modes. Shuttle can do it, so I'd say it IS engine-out tolerant.

Tell that to the Challenger crew families. Any kind of failure where they don't have time to separate the orbiter and glide to the emergency strip and the crew is dead, even if they and the shuttles internal capsule survive an explosion like Challenger's did. No 'chutes, no escape thrusters etc. etc. so it's a 300 mph dive into the drink from 50,000 feet or more. That doesn't even take into account the thermal protection system and foam isssues.

Thing's a death trap, which is why it's standing down.

[Nowhere]

Well...no. Failure of one of the Shuttle engines (not counting the SRBs) is (supposedly) survibeable.

PS. Drunk posting is haaaaard

[Dr Mordrid]

Well...no. Failure of one of the Shuttle engines (not counting the SRBs) is (supposedly) survibeable.

Only if it gets high enough to separate from the tank with enough velocity to glide to the KSC runway, and that's by no means certain.

[Nowhere]

They can also bail out (plus there are other landing places)

[Dr Mordrid]

Those 'other landing places' are in Spain etc., plus as noted if they don't get to a decent altitude neither chutes or glide does them a lick of good. What you need is a powered cabin ejection system (crew capsule ejects & comes down on mulitple chutes) which, along with ejection seats, didn't make the cut. The cabin ejection system could have saved the Challenger crew.

[cjolley]

...The cabin ejection system could have saved the Challenger crew.

Do you mean might?
There was an awful lot of high speed debris flying around up there.

[Nowhere]

Actually, I would agree with Doc - "could" is about correct.

There wasn't really any explosion during Challanger disaster at all, that might had flung high speed shrapnel around - what looked like explosion was basically just burning of fuel dumped from badly damaged fuel tank...behind it; what tore the stack apart (and into pieces) was aerodynamic force.

By that time ejected cabin would be probably far enough "sideways" so debris wouldn't be a big problem - small would decelerate rapidly, large one would stay out of the trajectory of the cabin due to inertia...and would decelerate quicker anyways, beeing probably much less aerodynamic - and this essentially happened, on some photos you can see the cabin "flying alone".

But that's beside the point...Shuttle wasn't designed with ejected cabin in mind, doing which is hard, and redesigning any craft for it even harder.

My point, Doc, was that Shuttle doesn't become unstable after losing just one engine. Then you dump external fuel tank in the apogee of your trajectory, and if there is no suitable landing site - bring the orbiter down to stable flight at relatively low speed and altitude and bail out on parachutes. For me that's also absolutelly valid abort mode.