Community > Forum > Official JP Aerospace Forum > Tandems

Tandems

Posted by: jpowell - Wed Nov 07, 2007 6:25 pm
Post new topic Reply to topic
 [ 6 posts ] 
Tandems 
Author Message
Space Walker
Space Walker
avatar
Joined: Tue Jan 18, 2005 11:12 pm
Posts: 137
Location: Sacramento, CA
Post Tandems   Posted on: Wed Nov 07, 2007 6:25 pm
The new airships have been rolled out and are up on the website.

www.jpaerospace.com

JP


Back to top
Profile WWW
Space Walker
Space Walker
avatar
Joined: Tue Jan 18, 2005 11:12 pm
Posts: 137
Location: Sacramento, CA
Post Video   Posted on: Wed Nov 14, 2007 6:25 pm
Video of the launch of the little (14 foot) MicroTandem is up.

www.jpaerospace.com

It's at the log section.

JP


Back to top
Profile WWW
Spaceflight Participant
Spaceflight Participant
avatar
Joined: Fri Oct 21, 2005 12:42 pm
Posts: 73
Location: Washington DC
Post    Posted on: Wed Nov 14, 2007 9:43 pm
nice! it looked from the video as if one baloon had more initial lift or something, like the vehicle flew tilted with one side higher than the other. was this the case? and how can you control something like that?


Back to top
Profile
Moon Mission Member
Moon Mission Member
User avatar
Joined: Fri Jan 09, 2004 11:52 am
Posts: 1384
Location: Exeter, Devon, England
Post    Posted on: Wed Nov 14, 2007 10:24 pm
Great Work!
Good to see another great video again also!

Rob G

_________________
> http://www.fullmoonclothing.com
> http://www.facebook.com/robsastrophotography
> robgoldsmith@hotmail.co.uk


Back to top
Profile WWW
Space Walker
Space Walker
avatar
Joined: Tue Jan 18, 2005 11:12 pm
Posts: 137
Location: Sacramento, CA
Post    Posted on: Fri Nov 16, 2007 6:07 pm
We're still looking at why it was angled in the first few thousand feet.
We meter the gas so there is the same amount in each balloon. We also check the balance of the vehicle about an hour before liftoff.

There are two leading candidates:

1. Uneven launch. We did some low altitude flight with a 18 foot test truss.
When we launched intentionally at an angle it would take a while for the vehicle to level out.

2. Different shaped balloons. We have found on the smaller balloon the inflated shape is not consistent. You can see in the video that the balloons look very different even though they have the same amount of helium. That has a big effect on the vertical airflow around the balloon during climb.

MicroTandem did level out after after about 3,000 feet above the ground. This implies number 1 however, I'm not sure that's the whole story.

The full size Tandem has a pumping system that can transfer gas between the balloons. This way we can correct any pitch problem in flight.
The pump will be on the second full Tandem flight. It's a little too much to have on the first flight so we'll need to very precise about weights and fill.

JP
www.jpaerospace.com


Back to top
Profile WWW
Moon Mission Member
Moon Mission Member
User avatar
Joined: Fri Jan 09, 2004 11:52 am
Posts: 1384
Location: Exeter, Devon, England
Post    Posted on: Sun Nov 18, 2007 2:37 pm
Talking about the shapes of the balloons, do you worry that environmental factors will hinder progress?

If small balloons are changing shapes and sizes on fairly good days at low altitudes there must be a huge worry about what will happen higher up and with more balloons. It must be hare to get coherent data if each balloon is performing differently?

Also how did the documentary go :) ?

_________________
> http://www.fullmoonclothing.com
> http://www.facebook.com/robsastrophotography
> robgoldsmith@hotmail.co.uk


Back to top
Profile WWW
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 
Moderator: jpowell
 

Who is online 

Users browsing this forum: No registered users and 8 guests


© 2014 The International Space Fellowship, developed by Gabitasoft Interactive. All Rights Reserved.  Privacy Policy | Terms of Use