Was there ever any plans or concepts of using three Titans in a heavy version instead of the solids for Titan III and IV? Just wondering what one would do.
There was also a proposed Titan II with solids around the base, presumably Castors. I've seen an artist illustration that I may have laying around somewhere. I think it was from the late 1980s.
Quote from: Blackstar on 02/18/2015 02:51 amThere was also a proposed Titan II with solids around the base, presumably Castors. I've seen an artist illustration that I may have laying around somewhere. I think it was from the late 1980s.Yes. Titan IIS, with four to ten Castor IVA solid motors. Up to four tonnes or more to sun synchronous orbit from VAFB. - Ed Kyle
'Barbarian' is a word that springs to mind although I think that was just a fat single core?p
Quote from: spacenut on 02/17/2015 09:21 pmWas there ever any plans or concepts of using three Titans in a heavy version instead of the solids for Titan III and IV? Just wondering what one would do. Of a sort. There was a general proposal for a Titan IIL during the early 1990s, which would have strapped two surplus Titan II first stages as boosters to a surplus Titan II core first stage. It wouldn't have been a very capable rocket by EELV standards, only able to lift 7.5 tonnes to sun synchronous orbit from VAFB. Only one of the core stage engines would have lit at liftoff, with the other igniting at booster staging. - Ed Kyle
Quote from: edkyle99 on 02/18/2015 02:49 amQuote from: spacenut on 02/17/2015 09:21 pmWas there ever any plans or concepts of using three Titans in a heavy version instead of the solids for Titan III and IV? Just wondering what one would do. Of a sort. There was a general proposal for a Titan IIL during the early 1990s, which would have strapped two surplus Titan II first stages as boosters to a surplus Titan II core first stage. It wouldn't have been a very capable rocket by EELV standards, only able to lift 7.5 tonnes to sun synchronous orbit from VAFB. Only one of the core stage engines would have lit at liftoff, with the other igniting at booster staging. - Ed KyleTo satisfy my curiosity, I looked at a Titan IIIC alternative using two Titan first stages as boosters. Assuming the same stretched stage used by Titan IIIA-C, and again assuming that one of the core "Stage 1" engines ignites on the pad and the other in the air at staging, I guesstimate 10.5 tonnes to a 28.5 deg LEO from the Cape or 0.9-0.95 tonnes to GEO using an upper Transtage. That compares with 12 tonnes and 1.043 tonnes for the early Titan IIIC variants. To get Titan IIIC performance, the first stages would need to have been stretched a bit more than they were for IIIC, to about Titan 34D size.So, why didn't Martin and the US Air Force take this path? My guess is that growth options were more limited. Titan IIIC was to be followed by Titan IIIM with longer solid motors to launch MOL. Titan IIIM would have boosted 17 tonnes to LEO while still using the same core stages as Titan IIIC. An all-liquid approach would have required changes to all of the stages to make such an improvement, and would have needed higher-thrust engines, or more engines. - Ed Kyle
Titan Barbarian using 3 shuttle SRB'shttp://i62.tinypic.com/v7yyqv.jpg
I'd think such a "Titan 4" core could have been designed with a similar thrust beam like the ET had so they'd mount properly. ?
Quote from: Lobo on 02/23/2015 11:35 pmI'd think such a "Titan 4" core could have been designed with a similar thrust beam like the ET had so they'd mount properly. ? no, the upper connection was on the second stage. Shuttle hardware on Titan was a non starter for many reasons. You keep on wanting to join NASA and DOD launch vehicles, it wasn't going to happen.They weren't "nice" SRB, they were overly complex and expensive and involved MSFC.
Titan IIS, with four to ten Castor IVA solid motors.
In order to make this happen, however, the core stage engines would had to have advanced quite a bit, likely requiring new engines altogether. If no throttling was used and only one core stage engine ignited at liftoff, thrust would had to have increased 45% over the existing LR87-AJ11 engine (to about 302 tonnes force (666 Klbf) at liftoff per core). If a new engine could be made to throttle so that all six engines could ignite at liftoff (allowing the core to subsequently thorttle down), liftoff thrust would only have needed to increase by 17% to 252 tonnes force (556 Klbf) at liftoff. Liftoff thrust needed to be 755 tonnes (1.66 Mlbf) for a gross liftoff weight ranging from 629 to 645 tonnes, ish.
So would there have been any benefit instead of going that route, to go the Angara route with essentially standard Titan III cores/engines? Tweak that core such that a central core could mount up to 6 other cores?And while the central core would probably have to be lit for lift off on such a configuration to have sufficient thrust, can the LR87 be shut down and then re-lit at SRB sep? It was air started after SRB sep on Titan III and IV, but could it be shut down after liftoff, and then re-lit?