Low Altitude Cluster Launch

Does anybody have experience with the LOC 4-29SS and 2 Estes F-15 motors? I would like to fly at a club sponsored PARK launch.
We have a 1200ft max altitude and G or less restriction. By my calculations it should work but a bit slow off the pad and AT F-20's might be a little too much for the park. Also how about the Estes F-15 in the AT Barracuda?

If I recall, F20s and other econojets actually have less impulse (but a lot more thrust) than F15s, so you might be able to fly those. You could also get adapters and try E20 clusters, or (no adapters) 4 Estes E16s.

I think the F20 is the EconoJet that has the most total impulse. You might try some sims for F23 or F27, which are also nice motors. Or as SC mentioned, try E20's with adapters. And his other suggestion for 4 E16's strikes me as a really nice option with lots of cluster action! How does that look in your sims?

SCrocketfan said:

If I recall, F20s and other econojets actually have less impulse (but a lot more thrust) than F15s, so you might be able to fly those. You could also get adapters and try E20 clusters, or (no adapters) 4 Estes E16s.

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Great advice.. I forgot all about those 29mm E's . It looks like I would have to use 4 as they appear to be bit slower coming up to peak thrust. And as thirstybarbarian says could be some great cluster action

The stock sim file says F42s should keep it under 1200 and be quick off the pad.

DizWolf said:

The stock sim file says F42s should keep it under 1200 and be quick off the pad.

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That is an option, But I have used those F-42's and they are pretty hot little motors. For the park setting I think a little slower burn (but safe) would be better. If you dont mind, How do the F20W motors look compared with the Estes F15's. Looking for about 800ft-slower burn.Using a nice big black oversized chute for a slow decent.(the rocket weight being adjusted to 31oz for the chute)

F42's sim to 1166, F20's to 1293. The F42's will give you a faster speed, but are 55N/s, the F20's are 60N/s
F23's go about 1,000 and are 52 N/s. F27's go 900, and are 49N/s only 35 MPH off the rail... slow, but doable.


I dont have the motor file for the f15s yet

DizWolf said:

F42's sim to 1166, F20's to 1293. The F42's will give you a faster speed, but are 55N/s, the F20's are 60N/s
F23's go about 1,000 and are 52 N/s. F27's go 900, and are 49N/s only 35 MPH off the rail... slow, but doable.


I dont have the motor file for the f15s yet

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I sure thank you for that Mr.DizWolf Those F27's look about right for what Im doing. After checking "thrust curve" it looks like the E16 and F15 have the same burn(to slow off the rail )unless I did a 4 motor cluster then Im adding the extra weight of the motors.So it might not be a safe choice.(the F burning a second longer but they both take 1/2 second to hit their peak) Looks like its time to get a program lol Too much thought going into this you think?

As of today I havent done the low and slow launch with the 4-29SS. Last Sunday though we flew with 2 G53's for a great flight. I want to fly that Barracuda on an F15-6 but the winds havent been good . Maybe today or tomorrow. Has anyone had a good launch with that motor and rocket combo? One recommended motor is the E11-3 so it makes me think it would be fine on the F15(estes)

I'd be leery of a Barracuda on an F15, except perhaps when it's perfectly calm. Even then, I think you'd want a -4 delay. How much does yours weigh? I've flown a 12oz Mustang on E16-6 and F15-6 motors - it's a bit slow off the pad, but nice flights, even in a moderate breeze.

Yes I agree. I am a bit hesitant also. It weighs 15.5oz. . I thought about shortening a bit but why do that? I picked up those F15-6 motors thinking I could use them at the park launch but I kept thinking it might not work. You are right also I should at least have the 4sec.delay. Also done a bit of searching around and see if anyone has done it and all i found was one fella who used the E16 that ended in a horizontal flight. We Dont want that so I will find good use for those F's Im sure. Do you have a good recommendation for something, park flyable , 1000ft, F15-6 ? "low and slow style" Thanks for the the input .
Ed

Heaviest I've flown is an SLS Laser-X on an F15-6, at 14 oz, and it deployed a bit late, so now I use a -4. The -6 delay is perfect for the Mustang, does about 1100', so any 2" diameter bird weighing between 10-13 oz should be fine. Low and slow just don't go along with the -6 delay on this motor.

If I was going to fly a 4-29SS low and slow I would rather go with 4 X D12-3 than 2 X F15-4. Roughly the same liftoff weight with more initial thrust.

Sim it first, of course.

J Blatz said:

If I was going to fly a 4-29SS low and slow I would rather go with 4 X D12-3 than 2 X F15-4. Roughly the same liftoff weight with more initial thrust.

Sim it first, of course.

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I sure do like like all the great advice on this forum. LOL Me just an old school flyer. Im sittin here thinkin how i still go over a launch a hundred times in my head just to figure out what delay to use or how many seconds i should set a timer for on a dual deploy(which i havent done yet) now that i think i have it figured out there is some new timer that detects apogee and you can pre set the main deploy in feet above the ground. Seriously im chuckling to myself now
still having a blast. Yep--gonna do the 4 D12-3's
Ed

View attachment 249077The owners of the property where we go to launch on "family day" are fencing us out. Weve found a new spot in the area but a little harder to hike it do to bushes and trees . So its going to be Clustered 24mm motors instead of those 29mm G64-10 motors. Looking for 24mm hardware under the tree this year for some low altitude clusters and still going to do the 4-D21-5 and 4 - F15-6 launches around January sometime. The Mirage should give some nice low launches on F50 motors. G64-4 also. Building in progress.