ESA ATL Plausibility Checks and Development

[wingman]

Originally Posted by Bahamut-255

Titan V 11022 - One SSME. One RL-10. Two 5-segment SRBs. Two 7-segment SRBs.

Titan V 12022 - One SSME. Two RL-10s. Two 5-segment SRBs. Two 7-segment SRBs.

Does that help to clear things up?

space shuttle main engine?

oh i got a artwork type pic of a Titan with Shuttle -Type SRB'S.

~edit~ found it.

[Michel Van]

This Titan V would look more like the Ariane 5 launcher
The core fuel tank (for SSME) is 5.4 meter ø, build like Shuttle ET (also build by Martin Marietta)
or even smaller in order to keep stage long for connect the Booster
those SRB are those UA1205 and UA1207 ?

so i can make calculation and graphics how it looks like

[Bahamut-255]

Originally Posted by e of pi

I got that. I meant performance.

Ah. Well that means:

Titan V 11022 - 38,000Kg

Titan V 12022 - 41,400Kg

[Bahamut-255]

Originally Posted by Michel Van

This Titan V would look more like the Ariane 5 launcher
The core fuel tank (for SSME) is 5.4 meter ø, build like Shuttle ET (also build by Martin Marietta)
or even smaller in order to keep stage long for connect the Booster
those SRB are those UA1205 and UA1207 ?

so i can make calculation and graphics how it looks like

It does resemble the OTL Ariane 5 LV, but it is a US design. The Core Stage diameter is actually set at 510cm for two reasons. It keeps the payload shroud synonymous with the STS Payload Bay. And allows you to fit the 5/7 segment SRBs with relative ease - 'I' Beams to help support it ala STS ET.

If you want to make some graphics. Go ahead!

[Michel Van]

Originally Posted by Bahamut-255

It does resemble the OTL Ariane 5 LV, but it is a US design. The Core Stage diameter is actually set at 510cm for two reasons. It keeps the payload shroud synonymous with the STS Payload Bay. And allows you to fit the 5/7 segment SRBs with relative ease - 'I' Beams to help support it ala STS ET.

If you want to make some graphics. Go ahead!

it could work,
i got tank size of 30 meter long x 5.1 meter ø
the UA1205 with 25.91 meter can be connected on this tank with no problem
lower connection at base of tank were engine thrust-structure meet tanks
and upper connection on inter-structure between LH2 LOX tanks.

the UA1207 with 34.5 meter long is problematic
upper connection must place on interstage of Core stage and Centaur-T
or you make the corestage like Ariane 5 EPC were inter-structure on top is extends, to connect the Solid booster

normal length of Titan V with Payload fairing is 53 meter, total length 63 meter

[Bahamut-255]

Originally Posted by Michel Van

it could work,
i got tank size of 30 meter long x 5.1 meter ø
the UA1205 with 25.91 meter can be connected on this tank with no problem
lower connection at base of tank were engine thrust-structure meet tanks
and upper connection on inter-structure between LH2 LOX tanks.

the UA1207 with 34.5 meter long is problematic
upper connection must place on interstage of Core stage and Centaur-T
or you make the corestage like Ariane 5 EPC were inter-structure on top is extends, to connect the Solid booster

normal length of Titan V with Payload fairing is 53 meter, total length 63 meter

Actually, the Core Stage is 40.00 x 5.10 metres. I'm using 'I' Beams, similar to the ones used on the Shuttle External Tank to help it handle the loads imposed on it.

The details are in the PM I sent you earlier.

[Michel Van]

here my version of Titan V

[e of pi]

Originally Posted by Michel Van

here my version of Titan V

That's really nice-looking, Michel! Bahamut, is that no-upper-stage version used very often? I suppose since it's sort of stage-and-a-half anyway with a hydrolox core the payload might not be terrible...

[Michel Van]

Originally Posted by e of pi

That's really nice-looking, Michel! Bahamut, is that no-upper-stage version used very often? I suppose since it's sort of stage-and-a-half anyway with a hydrolox core the payload might not be terrible...

about no-upper-stage version
the Titan IIID had no third stage to launch of heavy Spysat like KH-9 to KH-11

on my graphic the engines on Core stage modular system
it easy to adapt it, to drop one SSME+support after the mass of Core stage+payload is lower for one SSME thrust.
you lose more 3526 kg death weight

[Bahamut-255]

Thanks for the illustration Van! It really helps! If I have to nitpick though, it's three points:


1) The 5 segment SRBs use dummy segments in order to match the length of the 7 segment SRBs, as so to simplify the Core Stage somewhat.

2) I had expected the SRBs to be mounted a little lower, so the exhaust plumes wouldn't risk harming the SSME or the SSME support structure. Though I'll admit that being a regeneratively-cooled engine, it may not matter too much, while a protective cover for the SSME supports can resolve that department.

3) I hadn't actually factored in a no-Centaur Upper Stage, so it came as a small surprise to see it here.


But these really are niggling issues, and really don't detract from the work you've done. Which I thank you for again. Almost exactly what I had pictured in my head.

Originally Posted by e of pi

That's really nice-looking, Michel! Bahamut, is that no-upper-stage version used very often? I suppose since it's sort of stage-and-a-half anyway with a hydrolox core the payload might not be terrible...

Actually E, I hadn't factored in a no-Centaur Upper Stage in my works. But a small Upper/Circularisation Stage can work only on the single SSME Core Stages. I base this on the projected burn times of the single and dual SSME Core Stages - 420 and 225-240 seconds respectively. I would expect it to meet the - rather large - interim payload gaps between the Titan V 22400 and Titan V 11020 - and be built accordingly.

I'll work on it just as soon as I have the time.

[e of pi]

Originally Posted by Bahamut-255

2) I had expected the SRBs to be mounted a little lower, so the exhaust plumes wouldn't risk harming the SSME or the SSME support structure. Though I'll admit that being a regeneratively-cooled engine, it may not matter too much, while a protective cover for the SSME supports can resolve that department.

I suspect this comes from setting the forward mounting point on the 7-seg at the interstage, then working backwards. The LH2 tank is longer than the booster at that diameter, so the SSME ends up stick backwards. I'm not sure there's any particular legacy for the 5.1 m, so an increase to about 5.7 or so might allow the booster and LH2 tank lengths to synergize better. It may mean a step-down interstage to the 5.1 m of the Centaur-G/T and fairing, but that's not a huge deal.

Actually E, I hadn't factored in a no-Centaur Upper Stage in my works. But a small Upper/Circularisation Stage can work only on the single SSME Core Stages. I base this on the projected burn times of the single and dual SSME Core Stages - 420 and 225-240 seconds respectively. I would expect it to meet the - rather large - interim payload gaps between the Titan V 22400 and Titan V 11020 - and be built accordingly.

I'll work on it just as soon as I have the time.

Cool. I was a bit surprised to see it myself, I hadn't thought of operating it without the upper stage either,

[wingman]

has anyone done a "orbiter 2010 type" pic of the Titan V?

[Michel Van]

Originally Posted by Bahamut-255

Thanks for the illustration Van! It really helps! If I have to nitpick though, it's three points:


1) The 5 segment SRBs use dummy segments in order to match the length of the 7 segment SRBs, as so to simplify the Core Stage somewhat.

2) I had expected the SRBs to be mounted a little lower, so the exhaust plumes wouldn't risk harming the SSME or the SSME support structure. Though I'll admit that being a regeneratively-cooled engine, it may not matter too much, while a protective cover for the SSME supports can resolve that department.

3) I hadn't actually factored in a no-Centaur Upper Stage, so it came as a small surprise to see it here.

But these really are niggling issues, and really don't detract from the work you've done. Which I thank you for again. Almost exactly what I had pictured in my head.

THX see it as early Titan V Prototype version
for the Grafic i look on traditional Titan IIIC/E/D/ payload and take no-third Upper Stage
also the original form of UA1205 and UA1207

Originally Posted by Bahamut-255

Actually E, I hadn't factored in a no-Centaur Upper Stage in my works. But a small Upper/Circularisation Stage can work only on the single SSME Core Stages. I base this on the projected burn times of the single and dual SSME Core Stages - 420 and 225-240 seconds respectively. I would expect it to meet the - rather large - interim payload gaps between the Titan V 22400 and Titan V 11020 - and be built accordingly.

I'll work on it just as soon as I have the time.

bear in mind, Bahamut
the SSME or RS-25 is capable of throttling between 67% and 111% of thrust.
there allot to gain on Titan V22000 payload with this
also 1-1/2 stage were one RS-25 is drop the other brings core-stage in orbit, also with throttling on engine.

[Bahamut-255]

Originally Posted by e of pi

I suspect this comes from setting the forward mounting point on the 7-seg at the interstage, then working backwards. The LH2 tank is longer than the booster at that diameter, so the SSME ends up stick backwards. I'm not sure there's any particular legacy for the 5.1 m, so an increase to about 5.7 or so might allow the booster and LH2 tank lengths to synergize better. It may mean a step-down interstage to the 5.1 m of the Centaur-G/T and fairing, but that's not a huge deal.

I picked 5.1 m so that the payload fairing would match that of OTL Titan IV and be synonymous with the Shuttle Payload bay. On the single SSME versions, the payload shroud can be jettisoned at the 3-4 minute mark without the risk of it hitting the Core Stage. More payload that way - if not a huge amount.

Cool. I was a bit surprised to see it myself, I hadn't thought of operating it without the upper stage either,

Ah. Guess we both missed that one.

Originally Posted by Michel Van

THX see it as early Titan V Prototype version
for the Grafic i look on traditional Titan IIIC/E/D/ payload and take no-third Upper Stage
also the original form of UA1205 and UA1207

I think I will.

bear in mind, Bahamut
the SSME or RS-25 is capable of throttling between 67% and 111% of thrust.
there allot to gain on Titan V22000 payload with this
also 1-1/2 stage were one RS-25 is drop the other brings core-stage in orbit, also with throttling on engine.

Van. Stage-and-a-half was not on my mind when I designed the Titan V. Rather use the boosters and throttling range of the SSME(s) to both get as much payload up as is practically possible with each variant as well as limiting the maximum acceleration forces on it. Since I know full well what happens if the LV structure is overstressed. Read: Ariane 501.

I get a peak of ~6.7G assuming 109% rated thrust on the Titan V 22000 which I can cut to ~4.2G with the SSMEs throttled to 67%.

[e of pi]

Originally Posted by Bahamut-255

I picked 5.1 m so that the payload fairing would match that of OTL Titan IV and be synonymous with the Shuttle Payload bay. On the single SSME versions, the payload shroud can be jettisoned at the 3-4 minute mark without the risk of it hitting the Core Stage. More payload that way - if not a huge amount.

It's not too hard to rig it so that the fairing will still fall clear of the booster--check out the hinging of the solids on Japan's HII. I mean, the question is which is going to drive the diameter of the core--a desire to keep a constant-diameter stack for payload fairing jettison (essentially letting a legacy fairing drive the entire stack's design) or a desire to directly integrate the SRB attach point at the interstage while also avoiding the core sticking out below the SRB exhausts (letting the booster and core simplicity drive the design). Personally, since doing the latter doesn't really inhibit using the 5.1 m fairing, except for a slight increase in complexity, while it'll result in significant savings in complexity on the core, I'd favor it. On the other hand, it's your TL.

[Bahamut-255]

Originally Posted by e of pi

It's not too hard to rig it so that the fairing will still fall clear of the booster--check out the hinging of the solids on Japan's HII. I mean, the question is which is going to drive the diameter of the core--a desire to keep a constant-diameter stack for payload fairing jettison (essentially letting a legacy fairing drive the entire stack's design) or a desire to directly integrate the SRB attach point at the interstage while also avoiding the core sticking out below the SRB exhausts (letting the booster and core simplicity drive the design). Personally, since doing the latter doesn't really inhibit using the 5.1 m fairing, except for a slight increase in complexity, while it'll result in significant savings in complexity on the core, I'd favor it. On the other hand, it's your TL.

Perhaps, but I think I'll keep the 5.1 m core for now. I also have to remember the Hercules USRMs that OTL Titan IV switched to in the mid/late 1990s - and the ones proposed but rejected for STS. I can always use either of them to 'resolve' the issue.

[e of pi]

Originally Posted by Bahamut-255

Perhaps, but I think I'll keep the 5.1 m core for now. I also have to remember the Hercules USRMs that OTL Titan IV switched to in the mid/late 1990s - and the ones proposed but rejected for STS. I can always use either of them to 'resolve' the issue.

I think it's also worth noting that the fairing's going to need some redesign to properly clear the vehicle anyway--I think it can't just slide past the sides or it'll hit the solids. So it's gotta use some kind of mechanical or pyrotechnic (or mixed) system to get the fairing segments clear of the vehicle. So just beef that up a bit, and you can have your 5.1 m legacy fairing without having to extensively modify you legacy solids or complicate the design of the new core.

[Bahamut-255]

Originally Posted by e of pi

I think it's also worth noting that the fairing's going to need some redesign to properly clear the vehicle anyway--I think it can't just slide past the sides or it'll hit the solids. So it's gotta use some kind of mechanical or pyrotechnic (or mixed) system to get the fairing segments clear of the vehicle. So just beef that up a bit, and you can have your 5.1 m legacy fairing without having to extensively modify you legacy solids or complicate the design of the new core.

It won't hit the solids at all! They'll be jettisoned before the fairing is!

[e of pi]

Originally Posted by Bahamut-255

It won't hit the solids at all! They'll be jettisoned before the fairing is!

True, I suppose. Still, you'll want it well clear of the booster for good clearance, by at least several meters. If you're already designing it to do that, you can make it get around a 5.7 m core just fine. You're letting a trivial mechanical detail drive other, non-trivial engineering decisions.

[Michel Van]

i look on Titan V22000 (core 2 SSME and 2 RL-10 Centaur) variation

i got total minimum dry mass of 17670 kg for Corestage
so original 20000 kg mass look good, it's leave a margin
payload of 17000 kg get in 255 orbit,

About liftoff Thurst on V22000
if this is 1.2 x total mass of rocket (224746 kg) that's 3336 kN or 2xSSME on 65% trust
after launch on 142 seconds, the mass of rocket drop that only one SSME is needed
drop one SSME sound good, it work well, but it gain only 500 kg more payload.
but there is interesting alternative
one SSME on 109% thrust or 2310 kN and two GEM-40 with each 485 kN = 3336 kN
after 63 seconds the Gems are jettisoned and the SSME thrust reduce

so is there need for 2 SSME on Corestage ?
only if there are used as alternative booster for the Corestage
3 corestage: 2xtwo SSME, 1xone SSME with Centaur upper stage
get around 45000 kg payload in 255 km orbit