Results 41 to 50 of 55
-
03-06-2020, 22:03 #41
- Join Date
- Jun 2017
- Posts
- 841
Re: Crew Dragon will sooon be Launching
You do know that the Russians also had a moon program
up until this time they were ahead of the Americans in all aspects of space flight
There are a couple of very interesting You Tube vids of the Russian rockets and their moon program
The NK-33 and NK-43 are rocket engines designed and built in the late 1960s and early 1970s by the Kuznetsov Design Bureau. The NK designation is derived from the initials of chief designer Nikolay Kuznetsov. The NK-33 was among the most powerful LOX/RP-1 rocket engines when it was built, with a high specific impulse and low structural mass. They were intended for the ill-fated Soviet N-1 moon rocket. The NK-33A rocket engine is now used on the first stage of the Soyuz-2-1v launch vehicle.
About 60 engines survived in the "Forest of Engines", as described by engineers on a trip to the warehouse. In the mid-1990s, Russia sold 36 engines to Aerojet General for $1.1 million each, shipping them to the company facility in Sacramento CA.[13] During the engine test in Sacramento, the engine hit its specifications.
In the early 2010s the Soyuz launch vehicle family was retrofitted with the NK-33 engine – using the lower weight and greater efficiency to increase payload; the simpler design and use of surplus hardware might actually reduce cost.[26] TsSKB-Progress uses the NK-33 as the first-stage engine of the lightweight version of the Soyuz rocket family, the Soyuz-2-1v.[27] The NK-33A intended for the Soyuz-2-1v was successfully hot-fired on 15 January 2013,[28] following a series of cold-fire and systems tests of the fully assembled Soyuz-1 in 2011–2012.[29] The NK-33 powered rocket was finally designated Soyuz-2-1v, with its maiden flight having taken place on 28 December 2013. One NK-33 engine replaces the Soyuz's central RD-108, with the four boosters of the first stage omitted. A version of the Soyuz rocket with four boosters powered by NK-33 engines (with one engine per booster) has not been built, which results in a reduced payload compared to the Soyuz-2 launch vehicle.
https://en.wikipedia.org/wiki/NK-33
Now
I wonder what the genesis , history , and background of the SpaceX merlin engine is ?
The Russian rocket engine was way ahead of it's time !
-
04-06-2020, 07:56 #42
- Join Date
- Dec 2010
- Location
- Boland
- Posts
- 7,985
Re: Crew Dragon will sooon be Launching
If the russians were ahead in the space program, they would have gotten to the moon first...
The N1 rocket was huge, and complex and as history so eloquently shown, prone to failure. The moon lander was crude and the concept dangerous (requiring an EVA for the single astonaut to get into the lander from the command module). The whole program was not about science (which was a huge part of Apollo) but about getting to the moon.
Also the Merlin engine does not have heritage in the NK-33 at all, they work on completely different cycles. The new Raptor has more in common with the NK-33.
-
04-06-2020, 12:09 #43
- Join Date
- Jun 2017
- Posts
- 841
Re: Crew Dragon will sooon be Launching
The Russian scientists had to contend with a political system that did not always place the correct person in the needed position.
The Americans had to depend on the Russians to get American astronauts to the ISS -- for eleven years
The American moon program seemed to have collapsed ?
Seeing as you are knowledgeable about these engines perhaps you could explain the build history of the SpaceX Merlin
-
04-06-2020, 12:40 #44
- Join Date
- Jun 2009
- Location
- Bloemfontein/Molo Kenya
- Posts
- 6,102
Re: Crew Dragon will sooon be Launching
Did anyone see the clip of the "mouse" on the rocket?
https://www.express.co.uk/news/weird...w-Dragon-video
-
04-06-2020, 13:12 #45
- Join Date
- Apr 2014
- Location
- Western Cape, Cape Town
- Age
- 41
- Posts
- 2,476
-
04-06-2020, 13:15 #46
- Join Date
- Apr 2014
- Location
- Western Cape, Cape Town
- Age
- 41
- Posts
- 2,476
Re: Crew Dragon will sooon be Launching
Starlink 7 launch from early this morning, one of the rare occasions where the satlink does not cut out on the booster landing. This is this boosters 5th landing.
-
04-06-2020, 13:16 #47
- Join Date
- Jun 2009
- Location
- Bloemfontein/Molo Kenya
- Posts
- 6,102
-
04-06-2020, 13:47 #48
- Join Date
- Apr 2014
- Location
- Western Cape, Cape Town
- Age
- 41
- Posts
- 2,476
Re: Crew Dragon will sooon be Launching
Since SpaceX main first goal was cutting down launch costs with a focus reuse-ability when it came to engines they decided to keep it "simple".
So with the Merlin they went for a proven design that have been working since the 60's to get it working and then worked on improving it later on. So RP1 and LOX for fuel, classic open cycle like Saturn's H1 was the first goal. The weakest point of previous deisgn they identified was the turbopump assembly so they went for clean sheet new design to make it much more efficient, contracting Barber-Nichols to do it for them.
From there on they went through 4 iterations making various changes to the engines and switching to superchilled LOX etc and now the Merlin-D puts as almost much thrust as the Saturn's H1 engine but it is half the size and weight and more reliable at 1/30th of the cost.
With SpaceX it gets exciting if you start looking at their new Raptor engine, this is the holy grail of engines an affordable, working, reliable and reusable full flow staged combustion engine and to make it refuelable on Mars they went with a methane-LOX combo. But I will be typing for days to explain it all and still fail. This is an awesome video that simply explains the open cycle engines, oxidizer rich closed cycle like the soviet NK-15 and NK-33, fuel rich closed cycle the Space Shuttle RS-25 and the full flow staged combustion engine like the Raptor and the pros and cons of each.
-
04-06-2020, 13:52 #49
- Join Date
- Dec 2010
- Location
- Boland
- Posts
- 7,985
-
04-06-2020, 14:13 #50
- Join Date
- Apr 2014
- Location
- Western Cape, Cape Town
- Age
- 41
- Posts
- 2,476
Re: Crew Dragon will sooon be Launching
All mostly true, one thing is Soviets took a lot of short cuts that made them beat the US in the earlier goals but came back to bite them in the ass later on. For instance first manned orbit they didn't have a a reliable entry vehicle or human safe landing system; it was mostly the big Soviet steel balls of the cosmonauts that ensured they won. For instance Yuri almost did not survive that first historic flight, the uncontrolled landing hamster ball did not disconnect for the rest of orbitter and lucky broke loose before Yuri got friend, then Yuri had a few seconds to recover from is 8 to 9 G rentry, gather his big balls of steel at 30 000 feet he opened the reentry capsule and performed a skydive and parachuted to the ground seperate from the capsule.
So although they were ahead in a lot of areas they had one major problem, unlike Von Braun's basic design which was scalable in iterations by just adding more powerfull lower stages the Soviet Vostok and Soyuz designs were better and more efficient for earth orbit they could not be scaled up for a lunar mission.
And their solution was a whole new design in the form of the N1, which frankly was so complicated that if they continued with it it would have only successfully get to orbit in mid to late 80's when advanced computer power control system became available.
Bookmarks