Douglas D-890, D-895 and D-900 transport proposals (pre-CX-HLS)

[Jemiba]

On the photos of a wooden mock-up of the D-900, some differences are recognisableat least to my opinion. The cockpit glazing is
different, without doubt, I think, with a small row of windows above the main side windows, which have a different shape, too (BTW,
the top view of the general arrangement drawings shows an additional small window above the main windows, too, as in the D-890,
but not the side and front view). Additionally it seems to me, that the nose was somewhat more pointed here and the radome occupied
the whole of the extreme nose and not just its lower part. To be honest, the latter point may be just a delusion, due to the clearly
visible wooden structure of the mock-up.

 

[Stargazer]

Topic split. There is so much material on the D-890, D-895 and D-900 that I thought it was high time these had a topic of their own...

Thanks again Jemiba for your invaluable contribution to the subject!

 

[Jemiba]

Yes, it's the missing trim tab on the rudder. A real catastrophe. I don't know if we can wait that long...

I've corrected this embarassing error on both drawings of the D-895, using the shape of the DC-8
trim tabs, as the fin more or less has the shape of the DC-8 fin, too.

 

[circle-5]

Thank you Jens for the corrected D-895 drawings and both sets of D-900 drawings. Excellent observations throughout, particularly on the landing gear detail. I like the way you spend your vacations.

This kind of work is especially important, because warplanes (fighters and bombers) often get all the attention. Transports and airlifters are typically considered not sexy enough for most aviation authors and publishers. This forum is one of few places where these important aircraft get the coverage they deserve.

 

[Stargazer]

Couldn't agree more!

 

[aim9xray]

One point , that caused me some head scratching, was the landing gear. For the very short nose gear, somewhat similar to that of the C-130, maybe a sliding wheel well door could have been used. But the kind of retraction of the very wide tracked main gear legs (I was already pointed to this detail by Circle-5) and the use of two canoe shaped sponsons for each side suggests a different method of retraction, than in most other transports. Have attached a small sketch, how maybe it could work, but of course I’m not sure, if this could be a practical solution.

Jens, it is likely that the main landing gear trucks rotated 90 degrees during the retract sequence to fit in the fairings - much as they do on the C-17 (probably designed by the same engineers at Long Beach, brought out of retirement).

See youtube for the C-17 sequence here
http://www.youtube.com/watch?v=sDgM4x66LTM

or here:
http://www.youtube.com/watch?v=LSYltXaQbZI

 

[Jemiba]

Yes, seems to be more likely to me, especially as it would better explain
the two sponsons on each side. Many thanks for the clue !
(One leg retracting into the upper, the other into the lower position)

 

[aim9xray]

Well, that's a good start. The following are my opinions, for what they are worth.

- I think the upper fairings are for the offset structure for the landing gear struts, only.
- The gear trucks all rotate 90 degrees and rotate down and inboard to be stored in the underbelly fairings. All gear mechanizations are similar (saves money).
- The gear trucks should be moved inboard a bit (looking from the front).
- This puts the gear more nearly under the fuselage (vertical load) rather than further outboard which increases loading and stresses.
- Also - as much as of the gear structure as possible should be outside of the fuselage pressure vessel - see the C-17 animation.

 

[Jemiba]

Yes, even better. Due to the slightly elevated floor it would be easier to house the wheels.
I should just add, that this quite straddle-legged landing gear is shown in that form both
in the general arrangement drawing, as well as in a model photo, so I took it for granted.

 

[Jemiba]

And something more colourful: Mainly based on the paint schemes, that could be found on the C-141,
it's again nothing for the purists with regards to the numbers shown.
Still left to do is the colour profile of the D-895. I'm thinking about something like the "Fat Albert" in the moment.
Other ideas ?

 

[hesham]

Very nice my dear Jemiba.

 

[circle-5]

And something more colourful: Mainly based on the paint schemes that could be found on the C-141

Very good rendering of the D-900 in service, Jens. The D-900 would have been a much more versatile transport than the C-141, but the USAF could not have waited that long to retire the slow C-124.

Still left to do is the colour profile of the D-895. I'm thinking about something like the "Fat Albert" in the moment.
Other ideas ?

The D-895 was proposed as a USAF heavy logistics transport, with less than 50 conversions planned from the C-133 fleet. I can't imagine the USAF letting the Navy use even one of their precious airlifters for the Fat Albert support role, with the need for Air Force crews, maintenance taking place at AFBs, etc. The C-130 was widely used by the Navy, Marines and Coast Guard, which made it the logical choice.

A more appropriate color scheme for the D-895 would be a standard MATS livery, with (or without) a white roof and dayglo bands for arctic service. I know, it's not as exciting, but it's more realistic. If successful, USAF D-895s would also likely have served with the Military Airlift Command.

 

[aim9xray]

Wait. What?

The D-895 was to converted from existing C-133s and not built "all new"?

 

[circle-5]

Wait. What?
The D-895 was to converted from existing C-133s and not built "all new"?

That is correct. The idea was to upgrade the existing fleet of 50 Cargomasters (minus attrition) into the jet age, by "bolting on" a set of D-1920 (DC-8) wings and TF-33 engines -- sort of how Convair cobbled together the YB-60. I obtained a very basic document describing that process from the Douglas (now Boeing) archive.

I suspect that Douglas was either trying to sell anything they could (no matter how ungainly) or they were using the low-cost, less-than-perfect D-890 and D-895 options to make the all-new D-900 look even better. Given how much effort was put into the D-900 (multiple models, full-scale mockup, etc), I would say it was the latter.

 

[Jemiba]

... I can't imagine the USAF letting the Navy use even one of their precious airlifters for the Fat Albert support role, .....
A more appropriate color scheme for the D-895 would be a standard MATS livery, with (or without) a white roof and dayglo bands for arctic service.

Well, you're right, it'll probably be a bare metal scheme then. The dayglo bands were applied as standard ?

 

[foiling]

Terrific painting of the side view, Jemiba. Well done, as always.

 

[archipeppe]

Terrific painting of the side view, Jemiba. Well done, as always.

Quote!!


Jemiba, really nice job.

 

[circle-5]

... I can't imagine the USAF letting the Navy use even one of their precious airlifters for the Fat Albert support role, .....
A more appropriate color scheme for the D-895 would be a standard MATS livery, with (or without) a white roof and dayglo bands for arctic service.

Well, you're right, it'll probably be a bare metal scheme then. The dayglo bands were applied as standard ?

My understanding is that dayglo areas on fuselage, wings and empennage were added to increase the visibility of downed aircraft in the arctic wilderness for SAR crews. Some transports had dayglo, while others didn't. I'm no expert in that area, but I suspect it was tied to where each unit operated (i.e. Alaska with dayglo, Hawaii without).

Douglas always presented the D-890 and D-900 projects in a dayglo paint scheme. Since the D-895 was offered as an alternative under the same proposal, it would have almost certainly been finished in identical fashion.

 

[Jemiba]

I've chosen the bare metal look for the D-895, as I've found several photos of C-133 in this
guise here in Berlin at the Tempelhof airport during open days in the '60s/'70s.

 

[hesham]

Very nice drawing my dear Jemiba.

 

[circle-5]

Very nice rendering, Jens. MAC markings are indeed appropriate for the final years of the C-133X / D-895.

 

[foiling]

Love it.

 

[Stargazer]

Splendid work, Jemiba! Don't forget to copyright your work before uploading it, otherwise you may find that others will unashamedly use it or even pretend it's theirs!