Did Buran & Engeria have any advantages over STS?

[jimfromnsf]

It wasn't the engines, it is the lack of a boat tail or streamlining. The drag of the shuttle would be the same with or without the engines

 

[jimfromnsf]

"Seems like having the airlock in the cargo bay instead of the cabin on the Buran was considered a pretty good change. "<br /><br />All the shuttles do now also

 

[jimfromnsf]

shuttle carried the same amount OMS/RCS propellant. <br /><br />oxygen-sintin would have boiloff and ignition issues

 

[gunsandrockets]

[I did some googling and discovered the Buran has a radically lower landing speed than the Shuttle orbiter, 312 km/hour vs. 537 km/hour!]<br /><br /><The landing (touch down) speed of the Shuttle Orbiter is about 370 Km/hr. /><br /><br />I was speaking of the approach speed, not the post-flare touch down speed.<br /><br />The NASA source I used said the Shuttle Orbiter approach speed was 290 knots plus or minus 12 knots when the Orbiter was 6.9 miles from the runway at an altitude of 10,000 feet. I just converted the units into km/hour for easier comparison to the Buran.<br /><br />

 

[gunsandrockets]

<The Orbiter tail cone reduces the boat tail drag. The SSMEs are not a drag factor without the tail cone they are in the aero shadow.><br /><br />What is the subsonic L/D of the Shuttle with and without the tail-cone fairing? What would the L/D be if instead of the SSME in the tail there was a small hemispherical shaped tail-cone fairing (similar to the tail of the Buran)?<br /><br />

 

[gunsandrockets]

<shuttle carried the same amount OMS/RCS propellant.><br /><br />Actually a Shuttle Orbiter carries slightly less total combined propellant while bulking 12 tonnes heavier, and uses an OMS with 14% less ISP. Plus the Burn supposedly had plumbing so that additional propellant could be carried in the cargo bay. <br /><br /><oxygen-sintin would have boiloff and ignition issues /><br /><br />Seems like a pretty fair trade for the easier handling issues and the higher rocket performance. It's not nice to have people drop dead from hypergolic propellant fumes.

 

[gunsandrockets]

<Inaddition the hydrocarbons in the Buran OMS/RCS are more of a contamination problem for docking ops than are the hypergolic propellants.><br /><br />Really? That's surprising considering all the concern I had read about contamination from the hypergolic thrusters of the ISS during an EVA.

 

[gunsandrockets]

The crew arrangement of the Buran was also different than the Shuttle.<br /><br />Standard crew was 4 on the Buran, all on the upper deck and all provided with ejection seats. An additional 6 crew could be seated on the lower deck.

 

[willpittenger]

<blockquote><font class="small">In reply to:</font><hr /><p>Standard crew was 4 on the Buran, all on the upper deck and all provided with ejection seats. An additional 6 crew could be seated on the lower deck.<p><hr /></p></p></blockquote><br />Those on the lower deck probably had to do without ejection seats. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[gunsandrockets]

<Those on the lower deck probably had to do without ejection seats.><br /><br />Correct. Hence the standard crew size of 4 on the Buran compared to 7 on the Shuttle.

 

[earth_bound_misfit]

"Those were the cheap seats."<br /><br /><img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p> </p><p> </p><p>----------------------------------------------------------------- </p><p>Wanna see this site looking like the old SDC uplink?</p><p>Go here to see how: <strong>SDC Eye saver </strong>  </p> </div>

 

[rybanis]

Because of this post, I have laughed out loud.<br /><br />Also, thats pretty crazy that they launched Buran in a snowstorm. It must have been a pretty calm one, but still! <div class="Discussion_UserSignature"> </div>

 

[cbased]

that's right.<br />Winds up to 20m/s.<br />Landing was fully automatic. Fighting strong crosswinds Buran landed deviating 1 meter from the centre of the runway. This was first ever automatic spaceship landing of that kind and this fact is reflected in the Guiness Book.

 

[cbased]

Adding to the question of whether it was a better glider. Buran could deviate left or right for upto 2,000km during its descent. Does anyone know the corresponding figure for STS?

 

[gunsandrockets]

<Those were the cheap seats. ><br /><br />Hah! Gives a whole new dimension to 1st class seating vs. steerage.<br /><br />But does that mean all 7 seats in the Shuttle are cheap seats?

 

[gunsandrockets]

<Adding to the question of whether it was a better glider. Buran could deviate left or right for upto 2,000km during its descent. Does anyone know the corresponding figure for STS?><br /><br />The figure of 1,000 nautical miles pops to mind, but I'll have to look it up. Ah, this source says 2,040 km...<br /><br />http://www.braeunig.us/space/specs/shuttle.htm<br /><br />As I recall the crossrange requirement for the Shuttle was based upon a USAF requirement for a single-orbit return-to-launch-base abort cabability during military missions flown from Vandenburg AFB in southern Calfornia.

 

[christine16]

hmm quite strange, no one thinks Shuttle is better

 

[rocketwatcher2001]

Thank you for posting this thread. I have been wanting to for a few weeks but before I did, I wanted to do some research about Buran/Energia.<br /><br />I think the Russians devoled a better system than STS. The Americans were to married to the idea of reusablity, and it forced us to put the SSME's in the Orbiter, instead of developing a heavy launcher like Energia. The Energia/Buran could have supported an increadible space program if the Russians had the money and political will to take advantage of it. The STS could have too, but I think we would have needed a heavy lift vehicle like the Saturn V. Our Shuttle program would have competed with the heavy lift vehicle, but the Russian Shuttle went hand in hand with theirs.<br /><br />It's too bad that for the past 30 years, neither they or us, had such ambitious programs. <div class="Discussion_UserSignature"> </div>

 

[JonClarke]

The Buran was a more evolved system, and took take advanatage of the experience of the Shuttle. Of course it showed some improvements. <br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[willpittenger]

<blockquote><font class="small">In reply to:</font><hr /><p>The Americans were to married to the idea of reusablity, and it forced us to put the SSME's in the Orbiter, instead of developing a heavy launcher like Energia.<p><hr /></p></p></blockquote><br />It seems that Energia was designed with reusability in mind. The versions that actually flew did not have it, but from what I read the Soviets planned to have fly-back versions of the various Energia components. The same thing was debated for STS at various times. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[rocketwatcher2001]

<font color="yellow">....but from what I read the Soviets planned to have fly-back versions of the various Energia components. </font><br /><br />Maybe that would have been the best of both worlds. From what I can see, the U.S. wanted to build an airliner that went into orbit, but we never wanted to spend the time and money to develop it fully. The Sace Shuttle pushed the envelope a great deal, but I wish we had pushed it further. <div class="Discussion_UserSignature"> </div>

 

[PistolPete]

<blockquote><font class="small">In reply to:</font><hr /><p>The versions that actually flew did not have it, but from what I read the Soviets planned to have fly-back versions of the various Energia components.<p><hr /></p></p></blockquote><br />Well, a flyback version was planned, but I doubt that it would have ever been implemented. The "A Block", aka the boosters, were supposed to be recovered in a similar fashion to the SRBs: with parachutes.<br /><br />Here's a link about it: Energia Composition 1st stage <div class="Discussion_UserSignature"> <p> </p><p><em>So, again we are defeated. This victory belongs to the farmers, not us.</em></p><p><strong>-Kambei Shimada from the movie Seven Samurai</strong></p> </div>

 

[willpittenger]

Something going as high as STS's ET would need more than just a parachute. That would require a reentry system. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[rocketwatcher2001]

Will-<br /><font color="yellow">Something going as high as STS's ET would need more than just a parachute. That would require a reentry system. </font><br /><br />Perhaps I'm wrong, but don't you mean something going as *fast* as the ET, rather than as *high* as the ET? <div class="Discussion_UserSignature"> </div>

 

[gunsandrockets]

<Something going as high as STS's ET would need more than just a parachute. That would require a reentry system. ><br /><br />I take the claims for a recovery system of the Energia parts with a big grain of salt. Land recovery of huge parts like that would be really really impressive and no doubt very expensive.<br /><br />And you are mostly right about the core liquid-hydrogen stage of the Energia even though it did not reach the speed or altitude of the Shuttle ET.<br /><br />What's interesting about the Buran is that unlike the Shuttle which is a 2 + 1/2 stage to orbit system, the Buran is a 3 stage to orbit system.<br /><br />The Shuttle drags the 30 tonne mass of an empty ET right up to orbital velocity, it has to in order to keep the SSME fed. Once the ET runs dry it is ejected, and even though the ET has orbital velocity it's not in a circular orbit so it hits the atmosphere over the Indian Ocean. The Orbiter would hit the Indian Ocean too but for the OMS burn to circularize the orbit.<br /><br />The Shuttle derives one big benefit and suffers some huge penalties for it's 2-1/2 staging method of reaching orbit. The benefit is the SSME are kept for reuse. The penalty is that the 14 tonnes of the SSME plus the 30 tonnes of the empty ET have to get dragged all the way up to orbital velocity, which subtracts from the final payload the rocket system can place into orbit.<br /><br />The Buran on the other hand is a 3 stage system. The core liquid-hydrogen stage of the Energia booster burns out more than a minute before orbital velocity is acheieved. It is up to the oxy-hydrocarbon engines of the Buran to provide the final orbital velocity in addition to circularizing the orbit. Staging that way reduces the dead weight dragged up to orbit and increased the usefull payload. The penalty is the core stage liquid-hydrogen engines are expended.