Russians create versatile re-useable rocket engine.

[offsprey6]

<p>&nbsp;</p><p>http://www.space-travel.com/reports/New_Impulse_To_Russian_Rockets_999.html</p><p>&nbsp;&nbsp;&nbsp; <span class="BHL">New Impulse To Russian Rockets<br /></span> </p><table border="0" cellspacing="0" cellpadding="3" width="160" align="right"><tbody><tr><td>www.space-travel.com/images/angara-family-carrier-rockets-bg.jpg" alt="" hspace="0" vspace="2" align="right" /><br /><span class="BL">In the near future, Russia is likely to have a variety of Angara carrier rockets fitted with RD-191 engines, capable of deploying payloads of between 1.5 and 30 tons in low earth orbit.</span>

 

[tanstaafl76]

<p>&nbsp;</p><p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>So, SpaceX Merlin engine is fully re-useable, right?&nbsp; &nbsp;&nbsp;&nbsp; <br /> Posted by offsprey6</DIV></p><p>No, usually the wreckage is not recoverable.</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[job1207]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;No, usually the wreckage is not recoverable.&nbsp; <br /> Posted by tanstaafl76</DIV></p><p>Hey, the rd 191 has not yet flown. They have to work out their kinks as well. Space X could well git it right. We will have to see.&nbsp; </p><p>THe bottom line is this. If it goes into space, it will not wind up as a reusable stage. Afterall, putting a heat shield on it causes all sorts of problems.&nbsp;</p><p>So the ONLY the first stage will be recoverable, in all rockets. ( Unless they ever get the venture star or something similar up and running )&nbsp; </p>

 

[scottb50]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hey, the rd 191 has not yet flown. They have to work out their kinks as well. Space X could well git it right. We will have to see.&nbsp; THe bottom line is this. If it goes into space, it will not wind up as a reusable stage. Afterall, putting a heat shield on it causes all sorts of problems.&nbsp;So the ONLY the first stage will be recoverable, in all rockets. ( Unless they ever get the venture star or something similar up and running )&nbsp; <br /> Posted by job1207</DIV></p><p>I simply see no reason for a recoverable first stage if it is not a flyback vehicle. To begin with to recover engines, if that's the most imporant part you have two options land or sea landings both using parachutes, any thing more become too weight prohibitive. In either case the odds are very high the engine will be damaged by impact or severely compromised by saltwater. Factor in the dead launch weight of the parachutes and possibly air-bag landing aids and you take a huge chunk out of the payload capability.</p><p>Clearly Rutan has the right idea and probably has the vehicle on his drawing board as I write this. A White Knight on steroids, or at least with Shuttle power instead of jet engines. One idea would be a rail launcher with solid boosters releasing a liquid fueled flyback vehicle carrying the orbital stage. Another idea would be a Shuttle style launch with a combined solid and liquid system, easier to do, because the facilities are already in place, but probably less efficient then a rail launcher, as long as you have enough room to use it.</p><p>Where the Russian engine comes into it's own is in orbit where it can be used over and over, which would make it an ideal second stage engine.&nbsp; </p> <div class="Discussion_UserSignature"> </div>

 

[shuttle_guy]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I simply see no reason for a recoverable first stage if it is not a flyback vehicle. To begin with to recover engines, if that's the most imporant part you have two options land or sea landings both using parachutes, any thing more become too weight prohibitive. In either case the odds are very high the engine will be damaged by impact or severely compromised by saltwater. Factor in the dead launch weight of the parachutes and possibly air-bag landing aids and you take a huge chunk out of the payload capability.Clearly Rutan has the right idea and probably has the vehicle on his drawing board as I write this. A White Knight on steroids, or at least with Shuttle power instead of jet engines. One idea would be a rail launcher with solid boosters releasing a liquid fueled flyback vehicle carrying the orbital stage. Another idea would be a Shuttle style launch with a combined solid and liquid system, easier to do, because the facilities are already in place, but probably less efficient then a rail launcher, as long as you have enough room to use it.Where the Russian engine comes into it's own is in orbit where it can be used over and over, which would make it an ideal second stage engine.&nbsp; <br />Posted by scottb50</DIV></p><p>Of course for the Russian launch site the first stage recovery is on land. Their plan is to eventually&nbsp;have a flying recovered first stage. It would land down range "dead stick" (no propulsion) rather than fly back to te launch site which would force a heavy propulsion system.</p><p>The engine would not be an idea second stage due to the low Isper of the propellants being used (lower Isp than Lox/LH2).</p><p>They added hydrogen to the fuel (an equvalent of RP1)&nbsp;to eliminate the major problem of reusing a RP1/LOX engine: The RP1 leaves too much residue in the engine.<br /></p> <div class="Discussion_UserSignature"> </div>

 

[scottb50]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Of course for the Russian launch site the first stage recovery is on land. Their plan is to eventually&nbsp;have a flying recovered first stage. It would land down range "dead stick" (no propulsion) rather than fly back to te launch site which would force a heavy propulsion system.The engine would not be an idea second stage due to the low Isper of the propellants being used (lower Isp than Lox/LH2).They added hydrogen to the fuel (an equvalent of RP1)&nbsp;to eliminate the major problem of reusing a RP1/LOX engine: The RP1 leaves too much residue in the engine. <br /> Posted by shuttle_guy</DIV></p><p>I mentioned the second stage use because it was addressed in the article, as you say the basic design of the engine does not make it well suited for that type of use.</p><p>As for a heavy propulsion system for a flyback vehicle it would make sense to use that same system for launch if for no other reason then to lift it's own weight. By the time the flight reaches 50-60000 feet propellant burnoff would lighten the vehicle considerably. </p> <div class="Discussion_UserSignature"> </div>

 

[shuttle_guy]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>.........................As for a heavy propulsion system for a flyback vehicle it would make sense to use that same system for launch if for no other reason then to lift it's own weight. By the time the flight reaches 50-60000 feet propellant burnoff would lighten the vehicle considerably. <br />Posted by scottb50</DIV></p><p>There would be no advantage for using the air breathers to assist ascent. There would still be a reduction in performance of the vehicle&nbsp;because the added thrust would not off set the added weight.&nbsp;&nbsp;The performace loss would be even more if the system was to have enough fuel to assist&nbsp;the stage in a landing.</p> <div class="Discussion_UserSignature"> </div>

 

[vulture4]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>).They added hydrogen to the fuel (an equvalent of RP1)&nbsp;to eliminate the major problem of reusing a RP1/LOX engine: The RP1 leaves too much residue in the engine. <br /> Posted by shuttle_guy</DIV></p><p>Was the hydrogen added chemically, i.e. modifying the hydrocarbon, or do they mean that LH2 is injected into the engine? </p><p>Also, I am incredulous that the article neglects the Space Shuttle, which obviously has a reusable engine, albeit not an oil-burner. Of course, we are about to abandon the Shuttle ourselves, so I guess they cannot be blamed.&nbsp; Ammonia was also used in the XLR-99, another pretty successful reusable.&nbsp;</p><p>&nbsp; </p>

 

[MeteorWayne]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Was the hydrogen added chemically, i.e. modifying the hydrocarbon, or do they mean that LH2 is injected into the engine? Also, I am incredulous that the article neglects the Space Shuttle, which obviously has a reusable engine, albeit not an oil-burner. Of course, we are about to abandon the Shuttle ourselves, so I guess they cannot be blamed.&nbsp; Ammonia was also used in the XLR-99, another pretty successful reusable.&nbsp;&nbsp; <br />Posted by vulture4</DIV><br /><br />That's an excellent point. I seem to recall those SSME's being used quite a few times!! <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-tongue-out.gif" border="0" alt="Tongue out" title="Tongue out" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>That's an excellent point. I seem to recall those SSME's being used quite a few times!! <br />Posted by MeteorWayne</DIV></p><p>If I am not mistaken all liquid engines are capable of being fired more than once, and are tested prior to launch.&nbsp; The issue is not reusability of the engine, but a complete system that permits recovery and actual reuse.&nbsp; The hard part is not being able to fire and&nbsp; engine more than once, it is being able to recover it in a reusable condition without undue penalties in performance or cost to the complete launch system.&nbsp; I did not see anything in the article that indicated that the Russians really had anything new in this regard.</p> <div class="Discussion_UserSignature"> </div>

 

[trailrider]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>If I am not mistaken all liquid engines are capable of being fired more than once, and are tested prior to launch.&nbsp; The issue is not reusability of the engine, but a complete system that permits recovery and actual reuse.&nbsp; The hard part is not being able to fire and&nbsp; engine more than once, it is being able to recover it in a reusable condition without undue penalties in performance or cost to the complete launch system.&nbsp; I did not see anything in the article that indicated that the Russians really had anything new in this regard. <br />Posted by DrRocket</DIV></p><p>Correct! Whether you can re-use the engines depends on how ruggedly they are built.&nbsp; <em>Recovery</em> depends on designing the engine components rugged enough to withstand whatever the g-forces that will be encountered upon re-entry and landing.&nbsp; That is just what the Space Shuttle Solid Rocket Booster Decelerator Subsystem (SRB-DSS) was designed to do.&nbsp; Of course, the SRB's land on the water, and we don't know whether the intent is to recover the engines and whatever other components...tankage, etc., on land or not.&nbsp; I would presume that they <em>would, </em>but it does complicate things a bit, though they have experience at recovering the Soyuz capsules on land, and the "cargo" is very g-sensitive!</p><p>So, it's a matter of protecting the engines and associated hardware from re-entry heating, if it is that severe.&nbsp; Then you have to decelerate the package and orient it so that the orientation is correct.&nbsp; This is usually done by a drogue parachute that slows the package and orients it.&nbsp; Then you use main parachutes to lower the payload to the surface, whether water or land.&nbsp; You must then either cushion the payload or use retro-rockets fired just above the ground.</p><p>The devil is in the details!&nbsp; Don't know what they have in mind...</p><p>Ad Luna! Ad Ares! Ad Astra!<br /></p>

 

[scottb50]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>There would be no advantage for using the air breathers to assist ascent. There would still be a reduction in performance of the vehicle&nbsp;because the added thrust would not off set the added weight.&nbsp;&nbsp;The performace loss would be even more if the system was to have enough fuel to assist&nbsp;the stage in a landing. <br /> Posted by shuttle_guy</DIV></p><p>Not to be argumentive but if you have a first stage comparable to the Shuttle, Equivelent prpoellant tanks and SRBs the empty weight would be somewhere South of 250,000 pounds. If you consider composite construction a flyback first stage would be around 300,000 pounds, pretty much the landing weight of a 777. Figuring it would have to operate at takeoff power for about a minute and a half and, if the engines are restarted at 25,000 feet for less then two hours, considering cross range factors and reserves you would be looking at 20-25,000 pounds of fuel. Again, using the 777 as an example two 115,000 engines would more then accomodate a 300,000 pound landing weight, well above a 777 anyway.</p><p>If you consider the 230,000 pounds of thrust, at lift off, it more then carries the weight of the engines and fuel for the intitial part of the launch. Beyond that it is dead weight, but the added thrust when it is most needed would outweigh the penalty. </p><p>At 30 miles or so, the SRB's burn out and the second stage is released, continuing to orbit under it's own power. The first stage return for a conventional landing, servicing and relaunch. The biggest difference is the upper stage has to do more work and has to be larger and heavier, the other side is the first stage can be smaller and lighter. If, instead of getting rid of the SRB's and continuing to use the SSME's the upper stage would continue to orbit. </p> <div class="Discussion_UserSignature"> </div>