Looking at the tonnage of HCl from the 1st stage exhaust… well… it’s a bit more
than just a chloride based catalyst though…
Troy
From: arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx] On
Behalf Of Lloyd Droppers
Sent: Friday, 6 November 2015 2:37 PM
To: arocket@xxxxxxxxxxxxx
Subject: [AR] Re: [UK OFFICIAL] Re: Re[2]: Re: ORS-4 ("Super Strypi") Hawaii
launc...
Super Strypi Environmental Assessment pg 2-2 "All three stages of the Super
Strypi launch vehicle use a derivative of an Aerojet-manufactured commercial
launch booster propellant (Ammonium Nitrate Blend [ANB]) to carry payloads into
orbit. Table 2-1 lists the launch vehicle system characteristics."
<http://www.govsupport.us/ORSSSEA/Documents/FinalEA.pdf>
http://www.govsupport.us/ORSSSEA/Documents/FinalEA.pdf
The propellant is specified as ANB-3745 and ANB-3790 with no information on the
formulation or even propellants used but I assume with the name Ammonium
Nitrate Blend it uses at least some AN an oxidizer.
Lloyd
On Fri, Nov 6, 2015 at 4:18 PM, Anthony Cesaroni <acesaroni@xxxxxxxxxxx
<mailto:acesaroni@xxxxxxxxxxx> > wrote:
Or you can compound coated magnalium alloy and/or amorphous silicon.
Nonetheless the Isp hit is significant unless you co-crystallize a phase
stabilized AN with something else and include another energetic to make up for
the loss. None of this is trivial. As far as signature is concerned, chemicals
that are used to phase stabilize AN have a distinct signature themselves. Can
someone please provide a citation supporting the first stage booster in
question incorporates AN as an oxidizer?
Best
Anthony
Sent from my iPhone
On Nov 5, 2015, at 8:08 PM, Troy Prideaux <GEORDI@xxxxxxxxxxxxxxxx
<mailto:GEORDI@xxxxxxxxxxxxxxxx> > wrote:
You can substitute some of the Mg with Al which helps. Certainly the lower
density PSAN (compared to AP) in combination with the lower density Mg
(compared to Al) doesn't help either for performance or processing ease. You
need to include enough Mg to provide enough thermal energy in the chamber to
reliably melt the tough protective oxide coating of the Al.
Certainly the hygroscopic issues are definitely more prevalent with PSAN
solids than AP solids and Mg can contribute to that.
One thing you can do (without resorting to energetic binders) to assist with
processing is to substitute the hydrocarbon binder systems generally
incorporated into APCPs with more oxygen rich polyols like PPG provided the
reactive metal concentration is high enough. This can allow you to substitute
some of the low energy PSAN oxidizer with your binder which is an even lower
energy oxygen donor provided your metals can drag enough energy out from the
oxidation of such, but this will provide harder challenges in other areas
such as ignition and steady combustion.
Sounds like a nice anniversary nevertheless Brian!
Troy.
-----Original Message-----
From: arocket-bounce@xxxxxxxxxxxxx <mailto:arocket-bounce@xxxxxxxxxxxxx>
[mailto:arocket-bounce@xxxxxxxxxxxxx <mailto:arocket-bounce@xxxxxxxxxxxxx> ]
On Behalf Of BrianK ABQ
Sent: Friday, 6 November 2015 11:17 AM
To: arocket@xxxxxxxxxxxxx <mailto:arocket@xxxxxxxxxxxxx>
Subject: [AR] Re: [UK OFFICIAL] Re: Re[2]: Re: ORS-4 ("Super Strypi") Hawaii
launc...
Does anyone know the "guts" of the propellant?
Besides the phase change problem with AN and it's much lower Isp; you need to
(unless things have changed a lot) use Mg as the fuel, not Al. And Mg needs
extra processing (coating with linseed oil or such, well known from pyro
stuff). Otherwise it can absorb moisture during storage and ignite! That
would be bad for things. Then you have the constant worry (PSAN or not) that
thermal cycling will cause AN to undergo it's annoying phase changes thus
compromising propellant integrity.
But these days it's not surprising (sadly) to see a minimal enviro
