-
#340
by
mmeijeri
on 10 Nov, 2009 07:14
-
It was recently mentioned that Delta needs very strict alignment of its cores and solids. What causes the need for extreme precision? What bad things would happen if they were only roughly aligned? I'm trying to understand if the same thing would apply to Microcosm/Beal/Truax style, very strong and stiff pressure-fed rockets.
-
#341
by
Jim
on 10 Nov, 2009 13:17
-
It was recently mentioned that Delta needs very strict alignment of its cores and solids. What causes the need for extreme precision? What bad things would happen if they were only roughly aligned? I'm trying to understand if the same thing would apply to Microcosm/Beal/Truax style, very strong and stiff pressure-fed rockets.
Off centered thrust from a solid would be inefficient and require the core to counter, causing further inefficiencies.
-
#342
by
mmeijeri
on 10 Nov, 2009 13:36
-
So how accurate do the alignments have to be? Fractional degrees?
-
#343
by
Antares
on 12 Nov, 2009 23:42
-
Re RL10B-2 nozzles: the supplier is SNECMA, but I'm not familiar with any advance purchase of nozzles. There are lots of whole RL10s, not just nozzles, sitting around due to low flight rate.
-
#344
by
Propforce
on 16 Nov, 2009 14:36
-
Very good, sir. That precisely is or has been investigated. The performance boost is not for Ares V. Ares V is using the performance boost from the Delta IV Heavy Upgrade.
Well... this will all be OBE soon
-
#345
by
Propforce
on 16 Nov, 2009 14:57
-
Ronsmytheiii - 23/4/2008 5:43 PM
This may not be as sophisticated as the other questions, but what is a good book as an overview of the Delta IV system and its development? And if any other books of other launchers if know.
Rocketdyne had an internal and PR magazine called Threshold. There was one called "First Flight Edition" for RS-68 that gave a very good overview of the development of the engine. I can't find it on Google. Maybe a request to Canoga to get a soft copy of it.
Doubtful there's a book on this, exactly. I suggest looking at AIAA papers over the 1997-2004 and more recent time period.
Here's the new link to re-named PWR Engineering where you'll find many excellent technical articles on engine designs
http://www.pwrengineering.com/data.htmHere's the link to article on RS-68, published in 2002
http://www.pwrengineering.com/dataresources/EvolvedExpendableLaunchVehicleSystem-RS-68MainEngineDevelopment.doc
-
#346
by
kevin-rf
on 16 Nov, 2009 19:21
-
Drool,... Thanks Propforce
-
#347
by
Nick L.
on 27 Nov, 2009 04:21
-
Looking at the mission booklet for the upcoming WGS launch, it says that only two of the four GEM-60s have TVC, why not have it on all four?
-
#348
by
Skyrocket
on 27 Nov, 2009 05:40
-
Looking at the mission booklet for the upcoming WGS launch, it says that only two of the four GEM-60s have TVC, why not have it on all four?
It is simply not necessary.
-
#349
by
SpaceCat
on 05 Dec, 2009 17:06
-
In one of the EELV alternative threads, I recall PadRat saying the Delta IV requires its pad to be 'pretty much the most level surface on earth'......
I'm curious why that tolerance is so tight?
Sure, you want a level pad- but the millisecond the bird lifts, guidance is gimballing the engines, yes? So is the critical levelling requirement related to GSE/propellant connections.... cryo settling.... or what?
Advance thanks for your answers!
-
#350
by
Jim
on 05 Dec, 2009 17:38
-
In one of the EELV alternative threads, I recall PadRat saying the Delta IV requires its pad to be 'pretty much the most level surface on earth'......
I'm curious why that tolerance is so tight?
Sure, you want a level pad- but the millisecond the bird lifts, guidance is gimballing the engines, yes? So is the critical levelling requirement related to GSE/propellant connections.... cryo settling.... or what?
Advance thanks for your answers!
Not the pad, but the floor in the HIF for stage alignment
-
#351
by
JosephB
on 06 Dec, 2009 02:48
-
I wonder if any new info on base heating can be gleaned from this latest config with the RS-68 sandwiched between 4 solids?
I've read in other threads that clustering is going to be a major problem? (even without shuttle SRB's)
Beautiful looking launch by the way!
-
#352
by
Antares
on 06 Dec, 2009 17:05
-
You mean base heating on a potential NASA HLV? It's too geometry-dependent to translate to a different configuration. I'm sure they instrumented the heck out of the Delta IV boat tail on this launch.
-
#353
by
Propforce
on 07 Dec, 2009 21:32
-
I wonder if any new info on base heating can be gleaned from this latest config with the RS-68 sandwiched between 4 solids?
I've read in other threads that clustering is going to be a major problem? (even without shuttle SRB's)
Beautiful looking launch by the way!
You're probably thinking using the RS-68s for Ares V where six RS-68 is packaged in between two 5.5 segment of SRBs.
-
#354
by
Jim
on 01 Apr, 2010 22:12
-
Pretty sure that this is a Delta II second stage, can anyone confirm?
not any type of Delta hardware
-
#355
by
bobthemonkey
on 01 Apr, 2010 23:01
-
High Bypass Turbofan by the looks of things.
-
#356
by
Jim
on 01 Apr, 2010 23:07
-
High Bypass Turbofan by the looks of things.
Bingo
With a composite fan housing.
-
#357
by
Rabidpanda
on 07 Apr, 2010 07:07
-
Question:
Can the Delta IV heavy take a payload directly to EML 1? Or any langrange point for that matter? Has this been done before?
-
#358
by
mmeijeri
on 07 Apr, 2010 10:42
-
GEO is further delta-v wise, so it should be able to take substantial payloads to L1. As I understand it it would need a long duration mission kit to stay alive for long enough to do the insertion burn, unless the payload did that itself, which would not be a strange thing. If you used a quasi-ballistic trajectory that should require only stationkeeping capability.
-
#359
by
JosephB
on 02 Jul, 2010 19:42
-
Hypothetical question if I may, suppose DIVH is selected to launch a ISS & BEO Orion. Is it likely the crossfeed option (from booster to core) would happen?
What kind of extra performance could be expected? (assuming 68A) Thanks!
