Comments on: XCOR today took delivery of the cockpit assembly of its Lynx suborbital space plane.

By: Pzatchok

Pzatchok — Thu, 10 Apr 2014 14:31:39 +0000

If you notice that in both the Vulkyrie Bomber and its eventual child the Concord the windows are mounted directly into a frame structure.

On the Comet the windows were mounted into just the sheet metal skin. The Comet was one of the first passenger planes to use a stressed skin system for structural strength instead of a heavier frame type system.
All the stresses of flight were transmitted through the skin. When those stresses needed to go around a window they tended to collect and increase their effect at the squared off corners of the windows causing stress fractures and eventually the windows just fell out.

Why the Lynx has what looks to be a two layer canopy system I have no idea. Not a clue.
The bubble type canopy they show in the press release would do all they need a window or canopy system to do.
It will only be flying at any high speeds when the atmosphere is getting thin or not even there.
Anything they hit on the way up will crash through both layers. Anything they hit in space will pretty much do the same. Anything they hit on the way down will be just like any other typical bird strike.

I think the artists concept picture might be a little misleading from the eventual final ship.

Now those might be windows they bolt on for when they attach that large cargo/science pod onto the roof. If the pod over hung the cockpit and matted right to the top of the cockpit that would give it possibly 3 to 4 extra feet of room to use instead of having a pod that starts right after the cockpit.

By: Joe from Houston

Joe from Houston — Thu, 10 Apr 2014 04:24:38 +0000

In reply to Robert Zimmerman. It may be more cost effective to build a canopy with flat windows than one big curved bubble of glass like in an F-16. The other reason may be a safety related one in which if something poked a hole in a bubble of glass, it could lead to a more catastrophic type of failure than smaller flat windows separated by a strong metal frame.

By: Matt in AZ

Matt in AZ — Wed, 09 Apr 2014 23:45:35 +0000

In reply to Matt in AZ.

And I just remembered, the earlier mach-3 XB-70 Valkyrie bomber had a canopy arrangement very similar to the Concorde.

http://4.bp.blogspot.com/-lw5_Asy71xY/Ua7ujQDv23I/AAAAAAAABIk/MhY1klzVwEQ/s1600/XB-70-Valkyrie+1.jpg

By: Matt in AZ

Matt in AZ — Wed, 09 Apr 2014 23:38:22 +0000

I definitely would like to keep them in place during the mach-2 or mach-3 stage of its return. However, the Concorde had an outer canopy attached to the nose, that articulated downward during takeoff and landings. It also had squared window panels, so perhaps the dynamics are different in this situation – as opposed to a series of squared windows along the entire length of an early De Havilland Comet.

http://www.joelsilverman.com/data/photos/26_1DSC_0067_Concorde_SST.jpg

By: Robert Zimmerman

Robert Zimmerman — Wed, 09 Apr 2014 23:11:26 +0000

In reply to Matt in AZ. Yes, you are correct. My question now is why the interior and exterior layers? Also, even if the exterior squared windows are not essential for maintaining pressure, extensive engineering data still shows they fail. Would you want your exterior panels to fail on a suborbital flight?

By: Matt in AZ

Matt in AZ — Wed, 09 Apr 2014 23:04:27 +0000

I remember you’ve mentioned on The Space Show your skepticism of their squared canopy panels. Looking at the photo in your link and XCOR’s picture below, it appears there will be a rounded, pressurized, inner canopy beneath those squared exterior panels.

http://xcor.com/press/2008/images/08-03-20_lynx_ground_v02.jpg