Supersonic MODEL Rocket?

shreadvector said:

Does the F100-0 simulation file actually represent the real F100-0?

By that I mean:

1) What alleged total-impulse and thrust curve is in the sim file?

2) Does it correctly include the delay time? YES, I said delay time. F100-0 motors had a delay and an ejection charge with no cardboard cap on top. They had a very short delay (1 or 2 seconds) so that the motor would not blow through during burn sinc ethey were operating on the hairy edge of the design limits. The delay helped keep it intact and the ejection charge was the granular BP they normally used but it had a clear laquer covering the top so that it could blow upward and ignite an upper stage.

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Here's the what's on EMRR:

;F100 modified 8/11 to match NAR published delivered impulse, as tested 7/86
F100 27 150 0-4-6-8-10 0.050 0.108 F
0.147 20.000
0.230 49.850
0.521 94.990
0.669 48.000
0.756 20.000
0.930 0.000

Here's the engine data sheet:

Rocketjunkie said:

There were also G110 motors back then. Blue Thunder versions of the G55. Easy mach busters

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The Vulcan 24mm G200 was king of the castle. I think they claimed 130 n/s as well.

5x7 said:

The Vulcan 24mm G200 was king of the castle. I think they claimed 130 n/s as well.

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There was a Vulcan F675 as well, aparently:

https://rocketdungeon.blogspot.com/2008/03/vulcan-f675.html

The EGE said:

There was a Vulcan F675 as well, aparently:

https://rocketdungeon.blogspot.com/2008/03/vulcan-f675.html

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I saw a couple F675s flown but they never were sold. The G200 was 29mm, the G210 was 24mm. When I was a Vulcan dealer, I had 29mm G500s.

Just remember that a 100%G80 is the largest model rocket motor. Any G (or F) with an average thrust > 80 N is considered a high power motor.

Bob

I tower launched and recovered a modifed Estes Sizzler with
tumble recovery on an AT D24-7. Unloaded weight was 15 grams.
Rocksim put it at almost 900 fps. Was very surprised that the
fins did not come off.

billspad said:

Here's the what's on EMRR:

;F100 modified 8/11 to match NAR published delivered impulse, as tested 7/86
F100 27 150 0-4-6-8-10 0.050 0.108 F
0.147 20.000
0.230 49.850
0.521 94.990
0.669 48.000
0.756 20.000
0.930 0.000

Here's the engine data sheet:

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Looks more like an F45 to me.

Bob

I was always a big fan of the FSI ****** Dart. A few of mine are pictured including the only launch shot I ever got that wasn't just a frame of smoke.

Another rocket that had claims in the catalog to use for supersonic attempts was the SSRS/Crown Lasor-114 when powered without the payload section using an F67-12. I also flew that model many times in that configuration and recovered them using the full length alum. mylar streamers that CMR used to sell. You can see the nice flame from the low smoke composite F67 in the launch picture. That motor had plenty of grunt. Lasor-114 and Lasor-134 were my favorite high altitude models in the early 80's.

https://www.ninfinger.org/rockets/catalogs/crown82/82crown12.html

https://www.ninfinger.org/rockets/catalogs/crown82/82crown4.html



.

snaquin said:

I was always a big fan of the FSI ****** Dart. A few of mine are pictured including the only launch shot I ever got that wasn't just a frame of smoke.

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Thanks, Steve! I hope that you don't mind that I referenced your RockSim file for the ****** Dart and RX-1 Thruster earlier in this thread. Your file came in real handy and gave me valuable information when I built my clone of them a couple of weeks ago.

snaquin said:

Another rocket that had claims in the catalog to use for supersonic attempts was the SSRS/Crown Lasor-114 when powered without the payload section using an F67-12. I also flew that model many times in that configuration and recovered them using the full length alum. mylar streamers that CMR used to sell. You can see the nice flame from the low smoke composite F67 in the launch picture. That motor had plenty of grunt. Lasor-114 and Lasor-134 were my favorite high altitude models in the early 80's.

https://www.ninfinger.org/rockets/catalogs/crown82/82crown12.html

https://www.ninfinger.org/rockets/catalogs/crown82/82crown4.html



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I'd build clones of those too if I could find plans for them.

MarkII

bobkrech said:

Looks more like an F45 to me.

Bob

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An early example of average thrust as a marketing tool.

billspad said:

An early example of average thrust as a marketing tool.

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But 100 is such a nice, round, easy to remember number...

MarkII

bobkrech said:

Just remember that a 100%G80 is the largest model rocket motor. Any G (or F) with an average thrust > 80 N is considered a high power motor.

Bob

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Yup, slightly OT but once the G110 got mentioned, I could not let the G200 go unmentioned, as they were available around the same time.

Rocketjunkie said:

I saw a couple F675s flown but they never were sold. The G200 was 29mm, the G210 was 24mm. When I was a Vulcan dealer, I had 29mm G500s.

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Vulcan sold a G200 in both 24mm and 29mm version. I flew both 24mm and 29mm but preferred the 24mm version. The pic shows left to right, the 29mm G200, 24mm G200, and 24 mm AT G55, then a close up. I never saw the Vulcan G210 or G500 for sale
https://i694.photobucket.com/albums/vv306/5x7rocket/DSC00664.jpg
https://i694.photobucket.com/albums/vv306/5x7rocket/DSC00663.jpg

dedleytedley said:

Bob I'm sure you're right but I do think it will be a rocket worth building. If nothing else it should make an interesting noise. My Skyscoop does. Ted

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I for one would like to see pictues of your design Ted and flight pictures. Using that altimeter it would be fun to figure out the max speed This alsoi sound like a challenge to all the rocksim folks to come up with a mach uster or verry close designThe only thing that has ever tempted me about HPR is building a supersonic rocket
Cheers
Fred

I have a homemade 29mm Machbuster that I've sucessfully flown and recovered on an G78-7G. It's 17.4" tall and about 5oz unloaded.

It's made from a 13" length of thin-walled 29mm tubing and an ogive balsa nose cone from BMS. The fins were cut from 1/8" plywood from old clementine crates and such. The nose cone was hollowed out and partially filled with lead shot for stability; a washer and eyebolt where then epoxied on top. The fins were glued on with ordinary wood glue and given two fillets; the entire rocket was then covered with 3 thin layers of wood glue for strength, finishing, and a low Cd.

Pictures if you want em are here.

Recovery is a 2" by 40" streamer stolen from my Comanche-3. It's fast but safe; this was proved by numerous test-tosses in my back yard

I swing tested it with a G78 (125g) installed; this combination of high mass in a fairly short motor is the worst possible for stability. It was perfectly stable even at fairly low speeds.

I added a 1/4" lug and an ounce of tracking powder - flour - for flight. I launched it on the friday of NERRF 5. It disappeared off the pad and flew to a simmed 4000 feet and Mach 1.07. I saw the puff of powder at ejection, and though I never saw it in the air, I found it a quarter mile away in the exact same direction as ejection. The only damage was a small chip in the wood glue on the body tube.

According to my simulations (RASP code from the Handbook with my own motor files; details on that to be posted soon), there's a surprising number of motor that can reach Mach, so long as you use a medium-length, lightweight, stable rocket.

For 18mm motors, if you keep weight under half an ounce, a D21 will get to Mach 1.13.

For 24mm motors, the F32T will reach Mach 1.2 and the E30T 1.13 with a 1-ounce rocket.

For 29mm rockets, the G77, G78, G79, and especially the G80 are all good candidates, as well as of course the HPR options. (If you're willing to risk an 80-dollar case, the I200 can approach Mach 2 with a 3-ounce rocket.)

(Simulations assumed Cd=0.5 and Mach=1118 fps; simulated rockets were 2mm greater in diameter than the motor).

/incoherent rambling

Initiator001 said:

In the Rocketry Forum Archive, there is a thread titled "World Speed Record" (Or something like that ) that has a comment I posted with information about the Speed Trial flown out in the Las Vegas desert nearly 20 years ago.

You CAN do Mach 1 with an AeroTech D21 motor and the properly designed rocket.

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Initiator001 said:

In the Rocketry Forum Archive, there is a thread titled "World Speed Record" (Or something like that ) that has a comment I posted with information about the Speed Trial flown out in the Las Vegas desert nearly 20 years ago.

You CAN do Mach 1 with an AeroTech D21 motor and the properly designed rocket.

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I flew a Quest Screamin Demon on an Aerotech D21 reload, first flight. What a mistake! I never saw it again. It got gone so fast the exhaust trail went "invisible". Then, the smoke trail re-appeared waaaaay up there. I think the gap in the exhaust trail is when it was SUPERSONIC.

Anyone ever tried playing with nose cone shapes in simulations of minimum mass supersonic rockets? Yes, I realize that total mass is the most important factor. It looks like a von Karman would be best from this chart (1-4 = good to bad) although a 2:1 aspect ratio elliptical is the best at subsonic velocities, the chart doesn't show von Karman performance below mach 0.8, and I'd guess that most of the flight time will be spent at subsonic velocities.

The EGE said:

Recovery is a 2" by 40" streamer stolen from my Comanche-3. It's fast but safe; this was proved by numerous test-tosses in my back yard

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I'd use aluminized Mylar from "emergency blankets" and only launch on a sunny day to make the odds of seeing glints from the fluttering streamer better.

For 18mm motors, if you keep weight under half an ounce, a D21 will get to Mach 1.13.

For 24mm motors, the F32T will reach Mach 1.2 and the E30T 1.13 with a 1-ounce rocket.

For 29mm rockets, the G77, G78, G79, and especially the G80 are all good candidates, as well as of course the HPR options. (If you're willing to risk an 80-dollar case, the I200 can approach Mach 2 with a 3-ounce rocket.)

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Airframe weights without motor or loaded weight?

Years ago, maybe 15 years ago, I bought a small Estes rocket with BT50 and built it without the motor mount. I bought a 24mm F72 single use motor for it. I glassed the fins when I built it and added nose weight so the F72 would balance to the same point as the original 18mm motor. I launched it once with a B or C and got it back, then launched it with the F72 and it was never seen again. There was no smoke trail or anything, just BANG and it's gone. At high velocity I'm sure that the smoke trail gets so spread out that it's nearly invisible. This rocket simmed through WRASP to 1.4mach and something like 4000 ft. I'm sure WRASP isn't all that accurate, especially past mach, but I thought this was enough margin that I could be confident it would break mach. I would liked to have gotten it back just to prove that it didn't shred.

HOLY NECROBUMP BATMAN

Although technically not a model rocket, I flew an AeroTech G300 in a 6 oz rocket at Eldorado dry lake... Using the Chuck Mund photo documentation equipment, It flew to 2408 ft/sec. Mach 2.1 there was no delay or ejection charge, it was flown at night. the air friction visibly set the nose cone on fire. as a streak was seen for more then three seconds after burnout.It was first place at that launch. Second place was Jerry Irvine with a 1.5" J motor, don't remember average thrust, 2395 ft/sec. a virtual Tie.

The G300 was faster than a Vulcan motor with a much higher advertised thrust G. Drag race flown at Hartzel CO...

Just for fun and mental bubble gum. FYI, some of these posters were real o.g.'s

I believe the task can be accomplished with an F44.

Another good bump here... 2009 to 2018 to 2024 but still an interesting subject..

I'm wondering if a drone up high and near the flight path could detect the sound of a sonic boom.

Other than the technical interest of doing this otherwise the flight is not so interesting because you don't see it. The speed of sound is as they used to say "faster than a speeding bullet". A small rocket will just disappear on ignition without much evidence that it was ever there. Sure something the size of an Aerobee would be visible and some of the amateur rockets larger than M are visible, but something in the model rocket range would probably be too small to be visible.

bjphoenix said:

The speed of sound is as they used to say "faster than a speeding bullet".

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Only a very slow bullet. Most, not all, pistol rounds are in roughly the transonic range. Big, slow ones like .45 Auto are reliably subsonic. Virtually all centerfire rifle bullets, unless specially designed to be subsonic, fly Mach 2 or better. The fat part of the bell curve is in roughly 2300-3400 ft/sec, with 2600-3000 ft/sec probably having the meat of it.

Fun fact: In Yeager's autobiography, he said the X-1 fuselage was shaped like a .30 cal rifle bullet because they knew that was an object that managed to go supersonic without being shredded.

bjphoenix said:

I'm wondering if a drone up high and near the flight path could detect the sound of a sonic boom.

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Not over the sound of the motors and rotors.

Maybe using an fixed wing R/C aircraft and gliding around the rocket's flight path.

As an alternative, I think someone recommended using tethered balloon.

Still I think the sound of the rocket's motor is likely to drown out the "boom" especially for a small rocket.

SolarYellow said:

Only a very slow bullet.

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That quote was from the old TV series where they always showed what I thought was a .38 special revolver. I think even with Hi-Vel they were probably subsonic. But even a slow factory load of .38 special is still going fast enough that you aren't seeing it except under unusual circumstances.

OK who remembered the quote and the TV series- the old black and white episodes of "Superman".

jadebox said:

Not over the sound of the motors and rotors.

Maybe using an fixed wing R/C aircraft and gliding around the rocket's flight path.

As an alternative, I think someone recommended using tethered balloon.

Still I think the sound of the rocket's motor is likely to drown out the "boom" especially for a small rocket.

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I wondered how loud it would be. A model rocket that can achieve that velocity has to be relatively small so maybe its shock wave is also small. I remember when I grew up the local air base would occasionally have supersonic flight and the sonic boom from something that large was very loud, something you wouldn't miss.

A .223 diameter .22LR bullet makes a supersonic crack that's audible to the shooter if it exits the barrel at around 1150 fps or higher.

bjphoenix said:

That quote was from the old TV series where they always showed what I thought was a .38 special revolver. I think even with Hi-Vel they were probably subsonic. But even a slow factory load of .38 special is still going fast enough that you aren't seeing it except under unusual circumstances.

OK who remembered the quote and the TV series- the old black and white episodes of "Superman".

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More Powerful then a Locomotive...

SolarYellow said:

A .223 diameter .22LR bullet makes a supersonic crack that's audible to the shooter if it exits the barrel at around 1150 fps or higher.

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Even from Pistols the Hi-Vel 22s go Sonic and Crack.