Ye Olde Rocket Forum

Ye Olde Rocket Forum (http://www.oldrocketforum.com/index.php)
-   Plans & Publications (http://www.oldrocketforum.com/forumdisplay.php?f=4)
-   -   More thoughts on the Japanese Baka design - Estes plan #72 (http://www.oldrocketforum.com/showthread.php?t=7923)

the mole 10-11-2010 08:58 PM

The plan is here. http://www.spacemodeling.org/JimZ/eirp_70.htm

Doug Sams 10-12-2010 09:56 AM

Quote:
Originally Posted by the mole
How is this thing supposed to work? I see it ejects a motor pod which has its own chute. Then there's another chute up ahead, attached to the nosecone.

The motor tube is forward weighted, so when it ejects, the CG will shift aft to facilitate gliding, I think. But why the second chute? What deploys it? And if it glides, why's it need another chute?

Doug...stumped...

.

jdbectec 10-12-2010 11:12 AM

Quote:
Originally Posted by Doug Sams
How is this thing supposed to work? I see it ejects a motor pod which has its own chute. Then there's another chute up ahead, attached to the nosecone.

The motor tube is forward weighted, so when it ejects, the CG will shift aft to facilitate gliding, I think. But why the second chute? What deploys it? And if it glides, why's it need another chute?

Doug...stumped...

.



I've thought agout building this one for a while, If I'm correct the weight is for stability only, added around the motor tube as needed, I assume the rear ejection is to simulate the diving technique of the original.

A C6-5 or C6-7 could produce an "interesting" flight. ;)

CPMcGraw 10-12-2010 11:49 AM

Quote:
Originally Posted by Doug Sams
How is this thing supposed to work? I see it ejects a motor pod which has its own chute. Then there's another chute up ahead, attached to the nosecone.

The motor tube is forward weighted, so when it ejects, the CG will shift aft to facilitate gliding, I think. But why the second chute? What deploys it? And if it glides, why's it need another chute?

Doug...stumped...

.


Doug, there's only one chute, attached to the pod...

That "other wad" is wadding... :D

Doug Sams 10-12-2010 12:01 PM

Quote:
Originally Posted by CPMcGraw
Doug, there's only one chute, attached to the pod...

That "other wad" is wadding... :D
Craig,

Look at the forward end of the rocket on the second page. It calls out a PK-12 which is anchored at the rear of the rocket but stowed all the way forward. That's the 2nd chute I'm talking about. What ejects it? Does it come out with the pod at motor ejection? If so, when does the bird glide?

My take is the rocket boosts, then ejects the pod which shifts the CG aft allowing glide. But, if it's supposed to glide, why is there a 2nd chute, and what pulls it out, and when?

And if the rocket's not intended to glide, then why have all this added complexity?
...
Looking at the pic some more, the forward chute is indeed pulled out with the motor pod, so I guess it doesn't glide, but instead is supposed to dive after apogee, then have a late ejection, for dramatic effect.

But I think gliding would be a lot more kewl :) Of course, the ultimate would be to see a Hellcat or Corsair shoot it down :D

Doug

.

jdbectec 10-12-2010 12:16 PM

As per my earlier post, I don't believe it is intended to glide, but eject after apogee for dramatic effect.

IIRC, the real one had a rather fast glide rate.

But making a glider of it is food for thought :)

CPMcGraw 10-12-2010 12:34 PM

Quote:
Originally Posted by Doug Sams
... Look at the forward end of the rocket on the second page. It calls out a PK-12 which is anchored at the rear of the rocket but stowed all the way forward. That's the 2nd chute I'm talking about. What ejects it? Does it come out with the pod at motor ejection? If so, when does the bird glide? ...


Doug, I missed that one. I had to go look at the full image from JimZ to see it.

The Baka model is not a glider, at least not in the form shown in the plans. The attachment point for the 12-in chute is the very back edge of the model, so it only descends nose-down.

With some 'alterations', I bet it can be made to glide.

jdbectec 10-12-2010 01:12 PM

Quote:
Originally Posted by CPMcGraw
Doug, I missed that one. I had to go look at the full image from JimZ to see it.

The Baka model is not a glider, at least not in the form shown in the plans. The attachment point for the 12-in chute is the very back edge of the model, so it only descends nose-down.

With some 'alterations', I bet it can be made to glide.


Areed, it woud be interesting.

Doug Sams 10-12-2010 01:27 PM

Quote:
Originally Posted by jdbectec
But making a glider of it is food for thought :)
Alright. You make it glide, and I'll get a Squirrel Works Dogfight with a couple of Corsairs and chase after you :)

Doug

.

Doug Sams 10-12-2010 01:30 PM

Quote:
Originally Posted by CPMcGraw
The Baka model is not a glider, at least not in the form shown in the plans. The attachment point for the 12-in chute is the very back edge of the model, so it only descends nose-down.
What made me think the intent was gliding was that they split the noseweight between the motor pod and the nosecone, which left me thinking they were trying to get it trimmed a certain way, as if it was to glide.

Doug

.


All times are GMT -5. The time now is 11:02 AM.

Powered by: vBulletin Version 3.0.7
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.