For modern tiny accelerometer owners:

After reading about piston launchers, I got to wondering.
What is your highest recorded velocity from a single BP motor flight? No sim numbers, please!

A10?
C5?
C11?
D12?
Other?

I don't want to know about AP flights. I've seen plenty of data on all sizes and shapes of motors and rockets flown on AP motors.

__________________
I love sanding.

I'll have to go back through FlightSketch data to see if I can get you some answers to this. Highest velocity recorded from 13, 18 and 24mm BP motors only, single stage.

I will see what I can find. For the 24mm motors the data are likely not from anything near minimum diameter so they will underestimate what could be done.

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

OK — since I have the habit of posting my FlightSketch flights to the online log, it was fairly quick to go back through them to the point that FS Minis didn't have an accelerometer (late betas) and look for likely suspects for maximum speeds. As you'd expect these are models that are minimum diameter (or close) and light. Here's what I could find:

1/8A.5-1 - MMX payloader - FS Comp - max speed 100.4 ft/s. Data here: https://flightsketch.com/flights/2592/ This model is more minimum diameter for an FS Comp and kind of large for a performance MicroMax model

1/2A3-4T - Simple A Alt - FS Comp - max speed 176.5 ft/s. Data here: https://flightsketch.com/flights/1117/. This is a BT-5-based altitude competition model (but not a very competitive one. This flight was not pistoned.

A3-4T - Simple A Alt - FS Comp - max speed 340.4 ft/s. Data here: https://flightsketch.com/flights/1118/

B6-4 - Viking PL - FS Comp - max speed 311.8 ft/s. Data here: https://flightsketch.com/flights/2128/ This is a 3-fin Viking with the top inch or so made into a payload section.

C6-5 - Viking PL - FS Comp - max speed 405.7 ft/s. Data here: https://flightsketch.com/flights/2143/

The C5-3 is ill suited to high performance models because its delay is too short....so I don't have any comparable data for it. I did find that it gave a maximum slightly higher than a C6 when flown in the same model.

C11-5 - Rocketman small Miss Riley - FS Mini - max speed 250.2 ft/s. Data here: https://flightsketch.com/flights/2470/ While this is a minimum diameter model for 24mm it is heavy and with all the ridging on the 3D-printed nose cone and fin can, probably dragger than it could be.

I don't have any high-speed D12 data.

You didn't want composites, but the C12 really gives a kick to models normally flown on C6s. In an Alpha, the C12 can get it to over 530 ft/s vs 350 ft/s for a C6 in the same model. The fastest data I found when I was looking was an Alpha on a D16 - 657.3 ft/s. Data at https://flightsketch.com/flights/731/

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

Thanks. Got a piston launcher?

I'd love to know the difference in that Viking on a C6 with and without the piston launcher.

I forgot about the C5 only coming in 3 second delay, even back when BP was more potent. It's filled to the rim just to get 3s.

__________________
I love sanding.

Estes needs to make a 3.75" length 18mm motor like they do on 24mm.

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.
ALL systems are GO for MAYHEM, CHAOS, TURMOIL, FIASCOS, and HAVOC !

I'm sure our competition folks would love long 13mm and 18mm motors. I'd like to have some as well.

__________________
I love sanding.

I have some floating-head pistons that I've used mainly for NARAMs, yes. Percentage-wise they help the most for the lower total impulse classes. I don't know why I'd ever piston a C-powered model unless it had an egg aboard. And then it would likely be a C12 .

__________________
Bernard Cawley
NAR 89040 L1 - Life Member
SAM 0061
AMA 42160
KG7AIE

Amen to that, but would the casing have to be slightly thicker to handle longer burn time?


Bill

__________________
It is well past time to Drill, Baby, Drill!

If your June, July, August and September was like this, you might just hate summer too...

Please unload your question before you ask it unless you have a concealed harry permit.

: countdown begin cr dup . 1- ?dup 0= until cr ." Launch!" cr ;

Give a man a rocket and he will fly for a day; teach him to build and he will spend the rest of his days sanding...

Probably. The Quest D5's definitely had some heat issues and, IIRC, a few burned through the side of the casings.

__________________
I love sanding.

Still, I would like to see a C5-5 even in a longer and heavier casing. Maybe instead of 3.75" long, they can go with 3.5" or shorter per the original E15 24mm BP motor.

A 13mm B would also be nice.

With Estes working with the forthcoming Internats, maybe they might become interested in a 10.5mm BP motor?


Bill

__________________
It is well past time to Drill, Baby, Drill!

If your June, July, August and September was like this, you might just hate summer too...

Please unload your question before you ask it unless you have a concealed harry permit.

: countdown begin cr dup . 1- ?dup 0= until cr ." Launch!" cr ;

Give a man a rocket and he will fly for a day; teach him to build and he will spend the rest of his days sanding...