LOLL Supersonic Model Rockets

[nanchuanwushu1]

Is this rocket capable of taking a G motor instead of the E you have at the time? Or it could take to Es and reach at least 1500 ft more.. Is at least one of those solutions possible? Is your rocket capable of going even faster (in order to reach more height)?

[Calvertfilm]

@nanchuanwushu1 The body tube diameter means it couldn't take a G. But an E is possible.

[VERB65]

How do you know it went supersonic. I don't believe it sorry. But it's still cool. But not as cool as supersonic. Even a little vehicle such as that would of created a sonic boom of some sort. Sorry

[Calvertfilm]

@VERB65 The computer software estimated it would reach over 1,000mph and also we heard a 'crack' noise rather like a whip crack. The crack of a whip is due to the tip of the whip going supersonic. But we had no way of conriming the speed other than the noise it made.

[geekmanager2000]

@Calvertfilm Actually, you would not be able to hear a sonic boom/crack at the launch site since you would already be within the area of the sonic cone when the rocket goes super sonic. Those away from the launch site would hear it at the edge of the sonic cone passes them on the ground. The required distance from the pad to hear this is dependent on the altitude at which the rocket goes supersonic, and the shape of the cone. at low supersonic speeds the angle of the vertex of the sonic cone ...

[Calvertfilm]

@geekmanager2000 The rocket goes supersonic almost instantly.

[geekmanager2000]

@Calvertfilm ... is quite large. It is entirely possible that the rocket may be at sufficient altitude, and the cone so wide, that no one on the ground would be in a position to hear the boom/crack.

[Calvertfilm]

@geekmanager2000 Its a good point about the sonic cone but experienced rocketeers all felt it was going supersonic, that we could hear the crack, and the simulation software also bore this out. But we did have no specialist recording equipment, so it remains open for debate. Good point you made there.

[1983bfmv]

@VERB65

That easily surpassed the speed of sound.

[CobandPeaz89]

Brilliant!!! 10/10

[nicksynnz]

Nice launch..cool

[robotandlegolover]

omg you can hear the sonic boom! holy crap!

[jacktheripped]

I'm sure you can find mono cote rc airplane covering. It comes in a chrome finish among others. the flashing as the rocket comes down really helps to keep contact with the rocket. I put a band around the body and cover 1 fin.

this is a chrome mylar self adhesive found in hobby shops and pretty cheap, they have it in 4"x36" strips for trim too :)

[Calvertfilm]

@jacktheripped For sighting I also use a massive long streamer. I find there is no problem with these rockets when the streamer is that long. They are easy to spot, they come down quicker (so nearer to launch site) and any burn damage doesn't affect their performance like it may do a light plastic chute.

[jacktheripped]

lol first thing if you want to follow the flight is NOT to paint it blue

[Calvertfilm]

@jacktheripped Ah, but blue is my colour, so it has to be. I find them ok :-)

[Hambo19911]

where do you live it sounds like a jungle!

[Calvertfilm]

@Hambo19911 Ha, ha, yes well it is Hornchurch Country Park (several years ago now) where this flight took place. This is rather historic since it is the old Hornchurch Aerodrome used in WW2.

[r0ck3tsm0k3]

I didnt hear anything, and that does agree with theory because there is no mechanism by which the sonic boom could be heard on the ground for an object in a vertical flight that becomes supersonic above the altitude of the camera. For objects this small, the sonic boom does not sound the way one would think it does anyway... Just listen to a bullet some time.

Great rocket and great flights! (Despite the sonic boom misconceptions.)

[Calvertfilm]

@r0ck3tsm0k3 The sonic boom is heard within the mach cone, an area behind the object. So you wouldn't hear a boom above the object until the mach cone had gone past. But you would hear it from behind.

[MaldonadoMadness]

what was that shock cord made of

[Calvertfilm]

As far as I can remember (this was a few years ago now) it was regular shock cord, attached to a home made streamer (made from kite tails).

[MaldonadoMadness]

thanks, Im building a supersonic rocket right now

[Calvertfilm]

Keep us posted as to how it goes. Keep safe.

[pyrotechaholic]

try again genius.

[ytmachx]

That looks like a 1000mph!

[johnwarman54]

maybe you should have a little more certification that it actually DID go supersonic

Otherwise, cool vid!

[Calvertfilm]

If you have any ideas how we can measure it please let us know.

[Calvertfilm]

Bear in mind the rockets are light, so cannot carry anything as it will hamper their speed dramatically.

Speed guns don't register that fast.

Also, I doubt we'll be repeating the exercise as it was the late ninties when we flew these.

[propyropower]

nice vid - but when a rocket/object reaches that supersonic sound, do u hear a lil sonicboom of it ? :P, just curiousity

[Calvertfilm]

Sounded like a whip crack.

[Rcoketace15]

What is the average altitude of a D motor? What about a E?

[Calvertfilm]

This rocket desgin with a D motor should reach about 2,000 ft I guess tops. Estes claim a 2-stage version can peak at 2,500. The E motor was taking it up to 3,400 ft. But the best I got was a G motor in an Estes Maniac which normally takes Ds. This got to over 7,000 ft for a single stage rocket. It was sub-sonic at about 600mph.

[MonsterLD]

that was asome

[Calvertfilm]

Thanks. I've only flown 19 supersonic rockets and each times it gives me the shakes just before launch. They are so much fun (when they work without breaking up).

[Calvertfilm]

The motor was just able to fit inside the body tube. So that the mount withstood the acceleration it was glued in with epoxy glue. The rocket had plastic wings, as balsa would rip off, and metal was too heavy. All joints were glued with epoxy with nice thick wing roots. Top of the tube was also strengthened so the cone didn't collapse inside. Streamer used for quick recovery. Took me 6 designs to get to this working version.

[xmoda210]

that was crazy fast!! so did you just modify the engine mount to fit that in? great vid