Oxcart-Polaris air-lofted SLV

[DDE]

https://www.thedrive.com/the-war-zone/26251/cia-and-skunk-works-secretly-planned-to-turn-the-a-12-spy-plane-into-a-space-launch-mothership

Edited June 11, 2019 by DDE
Premature ignition; image borked

[wumpus]

You mean the M-21?  Scurries off to read article... er, no.  But still killed by the disasters encountered by the M-21.

My understanding from general back of the envelope math is that launching a rocket at mach 3 should reduce the amount of fuel needed in the rocket by about half (doesn't take into account that the first stage can approach vacuum efficiency throughout its flight).  On the other hand, there is the issue of supplying enough JP7 fuel (said to cost as much as fine scotch, and burn almost entirely running on afterburner) to get the AP-12 (nee SR-71) to both mach 3 and 20,000m.

Same issue that the stratolaunch has: it almost always makes more sense to stretch the first stage fuel tank out rather than use an air launch.  Of course with the stratolaunch, it *might* make more sense now that the plane is built and paid for, but it still has to compete with simple SRBs ringing the first stage (if thrust is limited from the extra fuel).

[Guest]

What is great about air launch schemes is their flexibility. Also, a small-ish solid space rocket is little different from a large missile, and can be stored in a similar way. The dV reduction is secondary to the fact you could possibly launch an A-12 based rocket from anywhere, in any direction, about as quickly as you'd launch a normal missile (or indeed, the M-21). The end result is that you can potentially have a small satellite in any orbital plane you want, anytime you want. For military/espionage purposes, such a system could be potentially useful. Hence why CIA was looking into it. The fact that you end up with a smaller rocket is just a nice bonus.

Edited June 10, 2019 by Guest

[mikegarrison]

7 hours ago, wumpus said:

JP7 fuel (said to cost as much as fine scotch)

JP7 cost about $3/gallon in 2005 ($4 in 2019 adjusted for inflation).

I want to know who your Scotch supplier is that you can get it for about a dollar a bottle!

[Guest]

So do I, mostly so I can give it a wide berth.  It might be "fine", but in a "fine structure" sense (that is, more water than whiskey... and that's if you're lucky). 

Edited June 10, 2019 by Guest

[benzman]

Here in Australia, my favourite whisky costs about US$450  per US gallon!

 

Edited June 10, 2019 by benzman

[wumpus]

15 hours ago, mikegarrison said:

JP7 cost about $3/gallon in 2005 ($4 in 2019 adjusted for inflation).

I want to know who your Scotch supplier is that you can get it for about a dollar a bottle!

That sounds better.  I've been going by some old article (probably popular mechanics or similar level) that presumably thought the stuff was classified and came up with that claim of price.  I wonder if it was true in the 1950s, when Scotland was likely broke and JP7 was new?

That still seems low for such a specialty item, and don't forget the factor of 10 markup when selling to the government* (that isn't all profit: all the paperwork and regulations involved can eat up the markup and then some), but a lot closer than my "fine scotch" claim.

* I think my number comes from selling floppy drives to the government (if not, a similar device where I was more than familiar with wholesale and retail prices).  The price included a ton of support and replacement provisions, along with fully custom mounting/enclosures (the *real* enclosures were often milled out of solid aluminum and cost far more than any electronics inside) and the government buyers didn't blink at the cost.

[mikegarrison]

JP7 was operationally expensive. The tankers couldn't use it themselves, so on many missions you needed tankers with JP7 to support the SR-71 and tankers with regular fuel to support the JP7 tankers.

I just found a 2016 price list that had JP7 at $9.46/gal, but I assume that as it became ever more of a specialty item, the price went up. The $3/gal price was exactly flat for 2002, 2003, 2004, and 2005, so I assume it reflected a pre-negotiated contracted price.

https://comptroller.defense.gov/Portals/45/Documents/defbudget/fy2004/budget_justification/pdfs/01_Operation_and_Maintenance/Overview_Book/43_Fuel_Rates.pdf

https://www.dla.mil/Portals/104/Documents/Energy/Standard Prices/Petroleum Prices/E_2015Oct8PetroleumStandardPrice_151013.pdf

[magnemoe]

On 6/11/2019 at 12:18 AM, mikegarrison said:

JP7 cost about $3/gallon in 2005 ($4 in 2019 adjusted for inflation).

I want to know who your Scotch supplier is that you can get it for about a dollar a bottle!

It was the oil who was costly as fine fine scotch, not the fuel. 
Suddenly it makes perfect sense. 

And yes you could probably launch with it using the setup for the recon drone however that did not work out so well. An rocket would probably be smaller in size. 
Dropping payload 18 km up at mach 3 would save you plenty however an F15 would probably be more practical.