06-19-2010, 02:56 PM
Bharat Karnad's book "India's nuclear weapons policy" mentions things that lead me to a different take on the significance of the 1.5 ton payload of A-III/V (A-V s referred to as A-IV) by BK. Keep in mind that BK in that book is extremely skeptical about the TN test in 1998. He was probably fully aware of the "fizzle" and hints that many BARC people themselves have the same opinion regarding RC.
The facts of interest are this:
1. For the 1.5 ton payload of A-3 and A-4 (now A-5) BK mentions the following 3 configurations.
8*125kt MIRV (A-5), 3*300kt MIRV (A-3) and 1*1MT single (A-5), all TN.
2. Indeed, 8*125kt for a 1.5 ton payload represents a very high level of miniaturization (compare with what is stated in the open abt trident I, say).
3*300kt represents a lesser degree of miniaturization.
3. The 1*1mt is interesting. Of course, this is untested. However, 1MT for a 1.5 ton payload is very poor miniaturization. Look at astronautix for details on 1960's soviet missiles. I have read there that one of them had a 5MT yield for a 1.7ton payload. I have also read on nuclearweaponarchive.org of 1MT for 450-500kg being achieved by the advanced powers well in the 60's and 70's.
4. It looks like this 1MT single warhead for 1.5 ton payload is a very conservative design. Something that is very heavy but something that they (DRDO, BARC and the users) have high confidence on. Also, despite all talk about MIRV's only this single very heavy payload config of A-3 is tested, and the same will be true for A-5 as well in the near future.
5. Given Chandraguptji's estimates of 1500kg being just the payload (not accounting for decoys etc- with real throwweight being 2500+ kg), this looks all the more plausible. It also explains why A-3 is arnd 3500 km and A-5 has around 5000km range.
6. Regarding, Israel, nuclearweaponarchive.org comments that they could have pure fission and sloikas without testing, two stage thermonukes without testing too, but with the caveat that the resulting two-stage TN would be heavy and unwieldy if it is to be reliable. Boosted fission with tritium gas was mentioned as unlikely for israel in the abscence of testing.
7. Maybe in our case too, there may have been this reliable, but heavy and unwieldy TN, still missile delivered by compromising on the missile's range in order to accomodate this heavy payload....
Opinions ?
The facts of interest are this:
1. For the 1.5 ton payload of A-3 and A-4 (now A-5) BK mentions the following 3 configurations.
8*125kt MIRV (A-5), 3*300kt MIRV (A-3) and 1*1MT single (A-5), all TN.
2. Indeed, 8*125kt for a 1.5 ton payload represents a very high level of miniaturization (compare with what is stated in the open abt trident I, say).
3*300kt represents a lesser degree of miniaturization.
3. The 1*1mt is interesting. Of course, this is untested. However, 1MT for a 1.5 ton payload is very poor miniaturization. Look at astronautix for details on 1960's soviet missiles. I have read there that one of them had a 5MT yield for a 1.7ton payload. I have also read on nuclearweaponarchive.org of 1MT for 450-500kg being achieved by the advanced powers well in the 60's and 70's.
4. It looks like this 1MT single warhead for 1.5 ton payload is a very conservative design. Something that is very heavy but something that they (DRDO, BARC and the users) have high confidence on. Also, despite all talk about MIRV's only this single very heavy payload config of A-3 is tested, and the same will be true for A-5 as well in the near future.
5. Given Chandraguptji's estimates of 1500kg being just the payload (not accounting for decoys etc- with real throwweight being 2500+ kg), this looks all the more plausible. It also explains why A-3 is arnd 3500 km and A-5 has around 5000km range.
6. Regarding, Israel, nuclearweaponarchive.org comments that they could have pure fission and sloikas without testing, two stage thermonukes without testing too, but with the caveat that the resulting two-stage TN would be heavy and unwieldy if it is to be reliable. Boosted fission with tritium gas was mentioned as unlikely for israel in the abscence of testing.
7. Maybe in our case too, there may have been this reliable, but heavy and unwieldy TN, still missile delivered by compromising on the missile's range in order to accomodate this heavy payload....
Opinions ?