Any info about AT I49 & I59 endburners?

I flew an I49 this past weekend in my Art Applewhite 12" Texas Special saucer. All I can say is WOW. A 7-second burn will put a smile on your face every time

One minor gotcha is that the grain must be bonded to the liner. Luckily, I had some 5-minute epoxy in my range box.

I was tempted to use a aftermarket plugged closure instead of shelling out for the closure, but since I had ordered it already I went ahead and grabbed it. Plus, I flew it at a NAR event so I guess the cert thing might have made a difference. :y:

NARpres did the button-pushing duties.

I will send those .eng files out tomorrow for you.

Nevermind, I found the files.

I'm going to be starting construction soon on a 12" 38 mm MMT saucer. I look forward to flying it on either the I49 or I59.

I flew my 54 mm saucer that you see in my avatar on a K185 this summer and all I can say is WOW! Saucers look great on low thrust long burn motors.

Mike

What would be the maximum amount of weight that the I59 can lift?

I have a 3-pounder that I would like to put one in, but I need to see if it would work. The initial 173 newtons would get it off the pad no problem, I'm just worried about the low thrust sustain phase.

Well, 59 newtons/5 = 11.8

then, 11.8/4.4 newtons/pound = 2.68 pounds,

so my guess is the maximum is 2.68 pounds.

I don't think I would use it on a rocket over 2 pounds though. Is this math right?

Mike

Your math is right, but ignoring a critical factor. The I59 has a much higher thrust off the pad (around 35lbs, IIRC) than the average, allowing it to lift as much as a 7 pound rocket without trouble. The sustain shouldn't be a problem, since it is already going fast enough to maintain stability at that point. I wouldn't fly it (or any other long burn) in high wind, but on a reasonably calm day, you should be fine up to 5 or 6 pounds on the I59.

BsSmith said:

What would be the maximum amount of weight that the I59 can lift?

I have a 3-pounder that I would like to put one in, but I need to see if it would work. The initial 173 newtons would get it off the pad no problem, I'm just worried about the low thrust sustain phase.

Click to expand...

I flew an I59 a couple of weeks ago in a LOC Nuke Pro Maxx stretched 10" for DD. It weighed 4.4lbs on the pad, loaded, ready to go. Based on the thrust curve, I figured this gave me a initial thrust to weight ratio of ~8:1. Wind was somewhere between 6-9mph. The rocket was a little over stable, so it did a little waggle off the pad. Very slight weathercock and the 8' rail was set vertical. Altitude on this flight was 5,081'. The motor had that nice White Lightning flame and smoke to give it a kick off the pad. After about a second and a half it went away and went to almost no visible flame and smoke but you could hear it burning for what seemed an eternity. Recovered almost exactly a half mile away. Hope this helps. The only thing I don't like about this motor it has no delay for tracking smoke.

Eric