Author Topic: Space Ship Two - General Thread (Read 755391 times)

docmordrid · « **Reply #420 on:** 05/19/2011 12:46 am »

Thought I heard someone say "choppy," (choppy air?) which may explain the oscillation.

Rocket Science · « **Reply #421 on:** 05/19/2011 01:24 am »

Quote from: docmordrid on 05/19/2011 12:46 am

Thought I heard someone say "choppy," (choppy air?) which may explain the oscillation.

I heard it a 2:40... maybe "copy"? The wing is going into areodynamic stall at that AoA and you see it rolling. The might have to work on a dampner system. You don't want to upset the high rollers...

For me it looked pretty good at this altitude. Should me more stable at deploy at a less dense atmosphere higher up and with thrusters if required. I guess this is the closest we will ever get to se the child of X-20 flying:)

docmordrid · « **Reply #422 on:** 05/19/2011 01:54 am »

IIRC X-20 never flew.

X-24's grandchild

Rocket Science · « **Reply #423 on:** 05/19/2011 06:51 pm »

Quote from: docmordrid on 05/19/2011 01:54 am

IIRC X-20 never flew.

X-24's grandchild

You do recall correctly!!:)
But she looks a lot more like the X-20 IMHO. The fuselage, the wing planform and with the twin vertical stabilizers outboard...

http://www.flickr.com/photos/13935339@N05/5370904998/sizes/l/in/photostream/
Remember a couple of years ago and little was going on... looks like good times. X-24A, a fave... "flying potato" kinda pug-cute...

Robotbeat · « **Reply #424 on:** 05/19/2011 07:15 pm »

Quote from: Rocket Science on 05/19/2011 06:51 pm

...kinda pug-cute...

(milk almost goes out my nose...)

Rocket Science · « **Reply #425 on:** 05/19/2011 11:28 pm »

Quote from: Robotbeat on 05/19/2011 07:15 pm

Quote from: Rocket Science on 05/19/2011 06:51 pm
...kinda pug-cute...
(milk almost goes out my nose...)

sorry about that....

kevin-rf · « **Reply #426 on:** 05/20/2011 01:48 pm »

Quote from: Rocket Science on 05/19/2011 11:28 pm

Quote from: Robotbeat on 05/19/2011 07:15 pm
Quote from: Rocket Science on 05/19/2011 06:51 pm
...kinda pug-cute...
(milk almost goes out my nose...)
sorry about that....

Yet another reason not to eat a spicy curry while reading NSF...

Jason1701 · « **Reply #427 on:** 05/21/2011 12:16 pm »

Ninth glide flight. Also Binnie's first SS2 flight.

http://www.scaled.com/projects/whiteknighttwo_spaceshiptwo_test_summaries

ChefPat · « **Reply #428 on:** 05/21/2011 01:03 pm »

Quote from: kevin-rf on 05/20/2011 01:48 pm

Quote from: Rocket Science on 05/19/2011 11:28 pm
Quote from: Robotbeat on 05/19/2011 07:15 pm
Quote from: Rocket Science on 05/19/2011 06:51 pm
...kinda pug-cute...
(milk almost goes out my nose...)
sorry about that....
Yet another reason not to eat a spicy curry while reading NSF...

Especially if I make it.

docmordrid · « **Reply #429 on:** 05/21/2011 09:25 pm »

Or if I make it - mine could strip paint

mr. mark · « **Reply #430 on:** 05/24/2011 09:48 pm »

It seems that the SS2 program could be in trouble! There are rumors that the engine tests of the hybrid motor have not gone well and that they may have to change to a liquid design which may mean design changes to SS2. It could cost the program several years.

http://www.transterrestrial.com/?p=34067

Rocket Science · « **Reply #431 on:** 05/24/2011 10:12 pm »

Quote from: mr. mark on 05/24/2011 09:48 pm

It seems that the SS2 program could be in trouble! There are rumors that the engine tests of the hybrid motor have not gone well and that they may have to change to a liquid design which may mean design changes to SS2. It could cost the program several years.

http://www.transterrestrial.com/?p=34067

Thanks for the article... I wonder if this problem extends into the SNC Dream Chaser as well now...

mr. mark · « **Reply #432 on:** 05/25/2011 03:56 pm »

What's truly mind blowing to me is that no one has commented on the possible hybrid engine problem here on this board. If it's true this shoots the whole project in the foot and could considerably delay or completely destroy any chance for near future winged designs as this could also affect Dreamchaser as well.

mr. mark · « **Reply #433 on:** 05/25/2011 04:03 pm »

Another glide test today. They are really moving along now. We'll have to see about engine development. Heard that Virgin Galactic hired former Spacex employee for liquid engine development.

"There is also a confirmed report that Virgin Galactic has formed its own propulsion team and hired the former director of SpaceX’s Texas engine testing facility — and an expert in liquid propulsion — as a member of it".

kevin-rf · « **Reply #434 on:** 05/25/2011 08:34 pm »

Could the "rough" ride be due something like that hybrids have a very large combustion chambers (compared to liquids) and this larger size leads to very large standing waves inside the chamber?

aka Thrust Oscillation part deux?

Skyrocket · « **Reply #435 on:** 05/26/2011 06:30 am »

Did the earlier larger Amroc hybrid motors like the H-1500 and H-1800 also suffer from thrust oscillations? These were IIRC larger than the SS2 motor and were test fired.

baldusi · « **Reply #436 on:** 05/30/2011 04:46 pm »

From

http://www.scaled.com/projects/rocketmotortwo_hot-fire_test_summaries

Quote

Fire: 06
Date: 24 March 11

Objectives:
Perform sixth full scale flight design RM2 hot-fire
Continue all systems evaluation
Continue fuel formulation evaluation
Continue nozzle evaluation
Continue motor structural evaluation
Continue Valve/Injector performance evaluation

Results:
All objectives completed. Performed increased duration hot-fire, including igniter performance, oxidizer flow and pressurization systems, data acquisition system measurements, structural evaluation, nozzle ablation, and fuel regression rate data collection. Determined stability levels.

It doesn't says much. But it would be read either way.

kevin-rf · « **Reply #437 on:** 05/30/2011 05:22 pm »

Quote from: baldusi on 05/30/2011 04:46 pm

It doesn't says much. But it would be read either way.

Though,

Quote

Determined stability levels.

Does say they are trying to find the engines sweet spot(s)...

Garrett · « **Reply #438 on:** 05/31/2011 01:13 pm »

Am surprised that these rumours of an engine problem aren't getting much coverage, even here on NSF. I know most of ye guys and gals are busy following the final shuttle missions and the exploits of Musk & Co, but if these rumours are true then won't there be some ripple effect on the economy of all space flight?

Does anybody have any more inside info? The space industry needs all the good publicity it can get, and all us space nuts were looking forward to Virgin Galactic flights next year. I would fear that any major problems with the engine could introduce a delay of a year or more. That won't look good in the media or to the taxpayer.

Danderman · « **Reply #439 on:** 06/01/2011 03:30 pm »

The obvious deal would be between SpaceX and VG/Scaled, where SpaceX would provide Kestrel engines to VG, and VG would provide composite structures for SpaceX. Yeah, I know that use of Kestrel would require a redesign for SS2, but the performance would be through the roof.