McDonnell Douglas GRM-29A

[Scott Lowther]

The next issue of Aerospace Projects Review (due to go to the printer in
a day or two) has an article on the McD Global Range Mach 29 Aerospace
Plane. This was a 1980's single stage to orbit lifting body, but with a
rather goofy engine arrangement... three SSME's in the tail, one in the
*nose*. It took off like a Harrier in a horizontal attitude, but
straight up.

The data available on it is a bit sketchy, but what I've got is in here.
it's an interesting design. A view of the whole issue is online at:

http://up-ship.com/apr/images/v5n2all.jpg



--
Scott Lowther, Engineer

"Any statement by Edward Wright that starts with 'You seem to think
that...' is wrong. Always. It's a law of Usenet, like Godwin's."
- Jorge R. Frank, 11 Nov 2002

[Henry Spencer]

In article >,
Scott Lowther > wrote:
>...This was a 1980's single stage to orbit lifting body, but with a
>rather goofy engine arrangement... three SSME's in the tail, one in the
>*nose*. It took off like a Harrier in a horizontal attitude, but
>straight up.

When the spec is adamant about "horizontal takeoff", but the engineering
clearly says you should take off vertically, people do what they can...
--
MOST launched 1015 EDT 30 June, separated 1046, | Henry Spencer
first ground-station pass 1651, all nominal! |

[Len]

Scott Lowther > wrote in message >...
> The next issue of Aerospace Projects Review (due to go to the printer in
> a day or two) has an article on the McD Global Range Mach 29 Aerospace
> Plane. This was a 1980's single stage to orbit lifting body, but with a
> rather goofy engine arrangement... three SSME's in the tail, one in the
> *nose*. It took off like a Harrier in a horizontal attitude, but
> straight up.
>
> The data available on it is a bit sketchy, but what I've got is in here.
> it's an interesting design. A view of the whole issue is online at:
>
> http://up-ship.com/apr/images/v5n2all.jpg

I was rather surprised to see this in print, Scott,
since it was rather closely held for a long time.
I did the original concept design for this configuration
--and all of the competing configurations by the other
companies--while a consultant at ANSER. The engine
arrangement is a little different from what you mention,
but I do not feel free to say more.

The overall project was derailed by false NASP promises
--not by technical barriers.

Best regards,
Len (Cormier)
PanAero, Inc. and Third Millennium Aerospace, Inc.
( http://www.tour2space.com )

[Len]

(Henry Spencer) wrote in message >...
> In article >,
> Scott Lowther > wrote:
> >...This was a 1980's single stage to orbit lifting body, but with a
> >rather goofy engine arrangement... three SSME's in the tail, one in the
> >*nose*. It took off like a Harrier in a horizontal attitude, but
> >straight up.
>
> When the spec is adamant about "horizontal takeoff", but the engineering
> clearly says you should take off vertically, people do what they can...

This project did not specify the mode of takeoff. However,
the main participants all believed that a winged approach with
a thrust-to-weight less than 1 (once in the air) offered
superior operational advantages without performance penalties.

Best regards,
Len (Cormier)
PanAero, Inc. and Third Millennium Aerospace, Inc.
( http://www.tour2space.com )

[Len]

(Scott Lowther) wrote in message >...
> (Len) wrote in message >...
>
> > I was rather surprised to see this in print, Scott,
> > since it was rather closely held for a long time.
>
> A non-classified (or at least, a document that was not labelled as
> classified) review of the GRM-29A was forwarded to me by Jess Sponable
> back in '98 or '99. If it's still classified... well... all I can say
> is that I got it through a public source and it's not labeled as
> classified. The Boeing RASV design was in the same review, and it's
> pretty declassified.

Oh, I wasn't challenging anything--just that I have not
kept up to date on the status.
>
> > I did the original concept design for this configuration
> > --and all of the competing configurations by the other
> > companies--while a consultant at ANSER. The engine
> > arrangement is a little different from what you mention,
> > but I do not feel free to say more.
>
> Might be a different version (the drawing sdo show two slightly
> different wing/body arrangements). The version desribed has three
> SSME's in the tail, two with extendable cones for high altitude, and a
> further SSME in the nose. All engines could pivot through at least 90
> degrees.
>
> > The overall project was derailed by false NASP promises
> > --not by technical barriers.
>
> My own view is that the added mass of the pivots, along with an SSME
> that's only used for 50 or so seconds, did not scream "SSTO mass
> fraction." But I don't have the detailed design data, so there ya go.

There were earlier versions that did not have some of
the problems that you mention. Again, I do not feel
free to say more.

Best regards,
Len