Dornier Do-27/28/228/Skyservant

[Weaver]

Picked up a RoG Do-28D today, and it got me wondering.....

Dornier evolved the Do-28's engine & undercarriage arrangement when they wanted to twin-engine the Do-27 but didn't want to screw up the STOL aerodynamics of the wing, so they fitted the twin engines on pylons either side of the nose, with a spatted mainwheel under each. They then found that the resultant Do-28A tended to bulk out, so they designed a new, boxy fuselage for it that became the Do-28D Skyservant.

This is a pretty unusual way of "twinning-a-single", so WHAT IF it was applied to other, similar types? I know there were some transport/bomber types between the wars that had this, some even featuring push-pull engine pairs on either side. Some obvious candidates would be the Storch and the Lysander, both of which could then be given "greenhouse" nose glazings. You might also turn a Beaver or Otter into an alternative Twotter. A less obvious, but interesting choice might be a parasol-winged fighter, such as a Pz.11.

Over to you....

[Weaver]

Nice one Apo! 

Doesn't have to be the Dornier's Lycomings: I was thinking of keeping the original engine type, so the Storch would have a pair of Argus's (Argi?), the Lizzie a pair of Mercury/Perseus etc....

[dy031101]

A while ago Lawman brought up an idea of using STOL utility aircraft instead of (as in real life) helicopters as a basis of an AEW type for an enlarged Invincible.

Real life didn't leave me much time for brainstorm exercise though, which would probably include the Skyservant as one of the candidates......

How workable would it have been to make the main landing gears of the Skyservant retractable somehow?

[jcf]

The 'other' Do 27 based twin..


The Do 29.





http://www.bredow-web.de/Luftwaffenmuseum/Transport/Dornier_DO_29/dornier_do_29.html

http://www.pilotfriend.com/photo_albums/timeline/postwar_mil/2/61.htm

http://airlandseacraft.blogspot.com/2009/02/dorniers-do-29-stolv-ground-breaking.html

[GTX]

A gunship D0-28 could be cool!

Regards,

Greg

[Weaver]

A while ago Lawman brought up an idea of using STOL utility aircraft instead of (as in real life) helicopters as a basis of an AEW type for an enlarged Invincible.

Real life didn't leave me much time for brainstorm exercise though, which would probably include the Skyservant as one of the candidates......

How workable would it have been to make the main landing gears of the Skyservant retractable somehow?

On a new or radically re-worked design, you could have them fold inwards like classic fighter gear. As a re-fit, probably best to design new engine pods and have the gear retract backwards into the space behind the engine. The pods look longer than the engine needs, but I don't know what's inside the back of them: could be just an empty aerodynamic fairing, or.......

[Mossie]

I guess you could use the approach with a standard Do.27, giving the original a little bit more oomph, maybe with a little extra stretch for a few more passengers.  I'm assuming that the Do.28 started out this way, before becoming a more substantial rebuild?  I've always liked the Do.27 & Do.28, I'll have to pick up the Huma & Revell kits when I see them.

[Mossie]

I was going to ask if there was any relationship between the Fi 156 Storch & the Dornier Do.27 as the two types are quite close in general characteristics & role.  I did a little sniffing on the net first & found the Fi 256, a Storch development that never got to production due to the end of the war.  On the face of it, this seems to close the gap between the two.  It seems that Dornier may well have resurrected & modernised a promising design?

Fi 256 'Super Storch'


Dornier Do.27


More info & pics on these two sites:
Translated page from Airwar.ru
http://www.piteraq.dk/flight/storch.html

[Weaver]

I think if anything, the Fiesler is "inspirational" more than a direct ancestor. The Do.27's wing is fully cantilevered with no bracing struts, and IIRC, the fuselage is monocoque not a covered tube frame.

This was the initial Do.28A/B, as you said, basically a Do.27 with two engines:



It tended to "bulk out" i.e. run out of space long before MTOW was reached, so they developed the Do.28D Skyservant to provide more options.

[Mossie]

I think if anything, the Fiesler is "inspirational" more than a direct ancestor. The Do.27's wing is fully cantilevered with no bracing struts, and IIRC, the fuselage is monocoque not a covered tube frame.

This was the initial Do.28A/B, as you said, basically a Do.27 with two engines:



It tended to "bulk out" i.e. run out of space long before MTOW was reached, so they developed the Do.28D Skyservant to provide more options.

Thanks Weave.  I'd say the Do.27 was just a generation ahead in the materials & structure it used?  Inspired, but heavily, the two are so similar in general configuration I'd imagine that Dornier had employed at least some of the same design team.  Either that, or given the brief 'build a modern Storch but don't fix what ain't broken'?

Thanks for the pics of the early Do.28, you know I never twigged that the A & B would be so different from the D model.  It rings a bell now I've seen it, I guess I'd never paid much attention before!

[dy031101]

On a new or radically re-worked design, you could have them fold inwards like classic fighter gear. As a re-fit, probably best to design new engine pods and have the gear retract backwards into the space behind the engine. The pods look longer than the engine needs, but I don't know what's inside the back of them: could be just an empty aerodynamic fairing, or.......

How about a trike?

The Dornier TNT (Tragfluegel Neuer Technologie, a converted Do 28D-2) testbed used the undercarriage from an Alpha Jet. IIRC, the gear was locked in the down position but it's easy to imagine it still being retractable.

I imagine that I would favour Weaver's idea of main landing gear retracting backward......

apophenia's idea might require some change in internal layouts- that's in addition to being worried about fitting a radar inside- or fuselage bulges for landing gear compartment (probably far easier to do, but I don't know enough to be sure).

[Mossie]

Does anybody have any internal pics of the Do.28's cabin?  I'm finding it hard to find any images, just a few on Airliners.net looking through the doors from a distance.

Another request, does anyone know if it was ever set up for CASEVAC/MEDEVAC & how this was arranged internally?  Pictures would be the holy grail, although I think I'll be lucky!

EDIT, I've partially answered my second request, it was used by the Swedish Red Cross as a Flying Doctor.  I thought I'd seen pics of it in Red Cross markings somewhere, found out it was one of the options on the original Matchbox issue.

[Green Dragon]

I did a trike gear Do28 back in the early 80's (inspired by the TNT) using engines from a Hasegawa Mitsubishi Mu2J and Alpha Jet gear from the Matchbox kit just glued to the fuselage sides. Been hunting for the wreck recently to bash into a cargo Bronco!

Paul Harrison

[redstar72]

Does anybody have any internal pics of the Do.28's cabin?  I'm finding it hard to find any images, just a few on Airliners.net looking through the doors from a distance.

See Do 28D-2 Skyservant cockpits here:
http://www.planepictures.net/netshow.php?id=493469
http://www.bredow-web.de/Luftwaffenmuseum/Transport/Do_28_Skyservant/do_28_skyservant.html

Here is a cockpit of Do 28-G92 (a Hungarian conversion with Walter M601 turboprop engines instead of piston Lycomings):
http://www.airliners.net/photo/Untitled-(Trener-Air)/Dornier-Do-28-G92-Skyservant/0337499/L/

And here is Do 27 cockpit: http://www.bush-planes.com/Dornier-Do-27and28.html

[redstar72]

Found a plan of Skyservant's passenger cabin: http://www.flightglobal.com/pdfarchive/view/1967/1967%20-%202256.html