Rocketry Planet

Ooo, look, a new propellant!

Designation: 8222
%Solids/%Metal: 82/0
Binder Type: HTPB
Isp (1000/14.7) 235.6
C* (ft/sec): 4817
Density (lb/in): 0.0589
T0 (oR): 4648
Gamma: 1.22
Molecular Weight: 23.33
Rate coefficient: 0.0687
Pressure exponent: 0.284

What is the "market purpose" for this motor? Ultimate "cheater" motor?

It seems to be a minor modification of E6 propellant in a coreburner configuration.

Old is new again.

One wonders if "new" Apogee motors will suddenly have this propellant?

Just Jerry

I'm dense. I'm not following what this means. What is a "cheater" motor?

This is a HPR motor from a certification perspective > 80 ns. I wonder about the market myself. Big average thrust very little total thrust for a G.

Look at the propellant weight.

I did. Is that significantly smaller than the weight of a large F and a smaller motor? I haven't checked yet.

In a simplistic (and crude) calculation I took the weight and the newton's and it appeared that a 62.5g motor would not have any more total thrust than the newly formulated G80 - so by that measure the new motor isn't a whole lot better than what's out there. I would think a G80 - with lower average thrust and longer burn would take the same rocket higher - but I could be wrong.

My only thought had been that using this motor which barely is a G plus a long burn F would get you something...

Did you get that information from the ISP portfolio? The specs look all but identical to Warp9 (8223AL) but with half the rate coefficient.

So, a fast-burning, SU, very small G motor - bit of a 'niche' product I'd have thought. If they shaved a few Ns and made it a full 'F' it'd be ideal for an 'F' boosted dart

G142-6,10,14 (S)
29 x 113 mm
Single Use Motor
84.3 Newton-seconds total impulse
173.9 Newtons Peak Thrust
135.9 Newtons Average Thrust

Propellant mass: 38.6 gm.

Propellant Key:
8222ALF Propellant

Motor Type Key:
S = Single Use


Note being single use the propellant mass is 38.6g. Therefore it is not "mailable", but just barely. If it had been 30g it would be mailable.

At the propellant mass used it is about as small a G as you can get (cheater motor) [AT 29mm SU 84.3G135.9-10-8222ALF>. That makes it unsuitable for most NAR contests.

Not sure about TARC. Is this the sort of motor a TARC person might need?

Being over 80n average it is not a CPSC model rocket motor, and I believe is treated as HPR for purposes of consumer certification.

If I had to say what the purpose for this motor was, it would be to show an instance of the single most wildly regulated motor on the planet, and I'm not kidding.

On the other hand, it doesn't know it. It thinks it is a cool woosh generator! Ahhh, blissful ignorance!

Just Jerry

yea, I would have preferred a butt kicking F which would be very handy for staging, loadlifting, etc. That is a helluva an ISP at 230+ , particularly in such a small motor where efficiency can take a hit.

I used to use the RMS G104 for a few niche things, it was bearly a "G" as well.

This new G142 I will try a few.
Hey Red Arrow Dave; Got any yet?

You can't use a HPR motor in TARC or NAR contests, but you can for Tripoli records; but no boosted darts allowed there.

Yeah, given its 29mm diameter and short burn, it would get its butt kicked for the G altitude record attempts by the new AT G80 with 137 N-s or a 24mm Ellis G37. And it's just slighltly too much impluse to be able to boost an F10 sustainer for a 2-stage record while staying within a G total impulse limit.

But it should do well (much better than a G104) for getting top speed in a mach-busting 29mm rocket since it's nice and light and short.