Intrepid-2A Scratch Build

[Bohica]

WOOOHOOO!!! That is definitely a success!!

 

[Delta-IV]

I love the idea but will it actually glide.

--- Ron

Today...just like the Space Shuttle.....only problem I didn't have any flare at the landing...

 

[AstronMike]

Update:

Flight Number 2 was made this morning.

The Combo launched with a F20-4W. At slightly past apogee the ejection charge released the re-built glider and it performed a slow left hand turn. The dive angle was steep (about 2 times what I wanted) and it landed 16 seconds after launch. Landing speed was estimated to be about 30 MPH.

Delta,

Glad to hear this worked better this time! I couldnt tell from your video exactly what the glider portion did, but it seemed you remarked that it did come down really rapidly.

FWIW, this past Saturday I also flew an F21 powered glider, my clunky old standy Astron EconoGlider. I didnt time it, but it likely was around 45 secs or so with no wind. Usual great sport flight, especially since its around 500 in sq wing area.

Looking at the video, I need to remove some ballast in the nose and increase the flap travel up a bit. https://www.youtube.com/watch?v=nHZauqCX4Mg

Yes, certainly so if every other 'moving function' worked correctly, which appears to be the case.

Heres another thing to consider, the AstronMike 45* rule. If you have to raise elevator/vons more than this amount to attempt to flatten out the glide, what usually occurs is that the severe upright angle of such devices then tends to create more drag rather than tail depression. In other words, you want the airflow to be smoothly flowing over the elevons, and with the least amount of drag with it. However, you can only remove some of the nose mass, otherwise you compromise boost stability.

If you end up needing more tail depression even if you lighten the nose a bit, the best workaround is to increase the size of the elevons rather than the angle they are raised to. If you can double the size of the elevons you may in fact need to *decrease* the raising angle, which is the best byproduct.

Many years ago I designed a rear eject job similar to a SkyDart, but more sinister looking. With a standard sized elevator, this still needed more depression, and angles around 65* were used. It worked, but I could notice that the ensuing glide was being 'washed out' by the increased drag (which probably gets added to base drag, bad bad). I then decided to tackle the depression problem in an unusual way, I redesigned the glider to where most of the wing itself raised slightly. Ended up raising about 65% of the whole area!! With a very slight angling, this worked MUCH better, and was very consistent. Thus, my Marauder design was born. And all these years later, Im still flying them in various sizes and materials. Back in 97, even sold some kits of these, which worked well for those who obtained them.

Back to the Intrepid now, sorry for rambling.

Ive deduced that your span and chord on the glider is roughly 18x24 inches. If so, Im going to go ahead and make one, slightly different than yours of course, and with my lightest stuff. Should end up doing at least 30 secs or more on a D12 if this works.........

 

[Delta-IV]

.....snip.......Ive deduced that your span and chord on the glider is roughly 18x24 inches. If so, Im going to go ahead and make one, slightly different than yours of course, and with my lightest stuff. Should end up doing at least 30 secs or more on a D12 if this works.........

Mike,

I forgot to post the glider plan info, here it is:

 

[Delta-IV]

Flight 4 today:

https://www.youtube.com/watch?v=d6MBVsxgmyA

I dedicated this flight to Jeff Zelna. Jeff was our Lead Engineer on the Delta II Upper Stage and Delta IV Payload Encapsulations...he passed on last Thursday night after celebrating our successful Delta IV Heavy carrying the DSP-23 spacecraft.

Jeff was wanting to see this and my Delta models fly...we were planning on doing this, this weekend.