Estes Ventris parachute deployment speed question

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Thirsty, I took a spent 29mm single use Aerotech motor, and cut a few rings out of it. A little masking tape and tadaa. 24 to 29mm adapter. The only thing larger than a D12 that I wouldn't launch it on would be an E9-4. Delay is waaay too long. 64 fps 'chute deployment speed.
 
If you're projecting 100' on this motor, will you even be going fast enough to be stable when it leaves the rod/rail? And how close to the ground will you be when the chute is fully open? It sounds like a D12 is too small a motor for this. Don't forget that when you adapt down to 24mm with a 29mm MMT, you'll be adding some weight for the adapter.
 
Velocity with the motor adapter without paint was about 29 feet per second off of the rod. If you look at post #18 on the first page, you'll see the launches I did. Heck, here they are again:

[video=youtube;3KwayAJUn_E]https://www.youtube.com/watch?v=3KwayAJUn_E[/video]

[video=youtube;xJhS8QZl5WU]https://www.youtube.com/watch?v=xJhS8QZl5WU[/video]

I have modifications in mind to make this low, mid, and high power capable. I'll post when I do.
 
I wouldn't launch a ventris on anything smaller than an E18/E20. to judge from your videos, you've got a good bit of weathercocking going on in a fairly light breeze(and that was unpainted). with paint it is going to be worse.
Rex
 
Rex, as I said, I have modifications in mind. Painted, it will only get a D12 on days with no wind. I'll make sure I video those flights too.
 
Tonimus said:
Velocity with the motor adapter without paint was about 29 feet per second off of the rod. If you look at post #18 on the first page, you'll see the launches I did. Heck, here they are again:

[video=youtube;3KwayAJUn_E]https://www.youtube.com/watch?v=3KwayAJUn_E[/video]

[video=youtube;xJhS8QZl5WU]https://www.youtube.com/watch?v=xJhS8QZl5WU[/video]

I have modifications in mind to make this low, mid, and high power capable. I'll post when I do.
Click to expand...

Actually, the videos shows the D12 is too small a motor for this. It seems to start arcing over as soon as it leave the rod, and in a no wind condition, you should get a vertical flight for at least some time. Does your sim software give you a speed to reach stability when leaving the rod? (I know rocksim does) 29 fps seems low to me for a stable flight.

I agree with Rex... This seems like a "minimum E" bird.
 
Wind was variable that day. 3-7 mph, hence the drift after the 'chute deployed. If it nosed over right off of the rod due to instability and not weathercocking, it'd have gone all the way over. So how many successful launches do I need before it's a proven concept?
 

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