Oddball, Experimental, or One-off

[onetrack]

A better photo below. It's not AI slop, the 4 wheeled undercarriage is what its fitted with.

 

https://www.airhistory.net/photo/191449/F-AZVC

 

The correct registration number of the surviving Croses EC-9 is F-AZVC. The registration of F-PYBC has been transferred to another aircraft, a Zenair CH-200 Zenith, and it is not clear whether the first Croses EC-9 has survived.

 

 

Edited June 11 by onetrack

[BrendAn]

20 hours ago, BrendAn said:

i think i read somewhere  it was designed for low ground pressure for soft ground. maybe summer alaska.

[rgmwa]

They must have had a special on wheels at Bunnings that day. Saves having to figure out where to put the spare tyre anyway.  Good thing they had the foresight to add a tail wheel as well. 

[red750]

The de Havilland DH.92 Dolphin was a 1930s British prototype light biplane airliner designed and built by the de Havilland aircraft company.

 

The Dolphin was designed as a modernised version of the de Havilland Dragon Rapide, incorporating ideas from the company's DH 86A and de Havilland Dragonfly but using new main assembly designs. It had a DH 86A-style nose to accommodate two crew side by side and increased span wings of unequal span, Dragonfly-like. It first appeared with the trousered undercarriage of these earlier biplane transports, but a retractable landing gear, rather like that of the DH.88 Comet was fitted before flight. Onboard air-stairs were one of the passenger access novelties. It was powered by two 204 hp (152 kW) de Havilland Gipsy Six piston engines. Fuel tanks were in the wings, as in the Dragonfly, to avoid the fire hazard of the Rapide's engine nacelle tanks.

 

One prototype was built and first flown on 9 September 1936. Geoffrey de Havilland's log shows that he flew it only once more. No others were built as it proved to be too heavy structurally and the prototype was scrapped in December 1936.

 

 

The only photo of the Dolphin on the internet.

 

[440032]

On 11/06/2026 at 11:16 PM, onetrack said:

A better photo below. It's not AI slop, the 4 wheeled undercarriage is what its fitted with.

 

One of my RC models has 4 wheels. No steering, but I can steer it around reasonably. It's weird but it works.

[red750]

The Douglas DC-4E was an American experimental airliner that was developed before World War II. The DC-4E never entered production due to being superseded by an entirely new design, the Douglas DC-4/C-54, which proved very successful.

 

Many of the aircraft's innovative design features found their way into the Nakajima G5N bomber after the single DC-4E prototype was sold to a Japanese airline and clandestinely dismantled for study by Nakajima at the behest of the Imperial Japanese Navy.

 

The design originated in 1935 from a requirement by United Air Lines. The goal was to develop a much larger and more sophisticated replacement for the DC-3 before the first DC-3 had even flown.

 

Such was the initial interest from other airlines, that American Airlines, Eastern Air Lines, Pan American Airways and Transcontinental and Western Air (TWA) joined United, providing $100,000 each toward the cost of developing the new aircraft. As cost and complexity rose, Pan American and TWA withdrew their funds in favor of the Boeing 307 Stratoliner, which was anticipated to be less costly.

 

With a planned day capacity of 42 passengers (13 rows of two or more seats and a central aisle) or 30 as a sleeper transport (like the DST), the DC-4 (as it was then known) would seat twice as many people as the DC-3 and would be the first large aircraft with a nosewheel. Other innovations included auxiliary power units, power-boosted flight controls, alternating current electrical system and air conditioning. Cabin pressurization was also planned for production aircraft. The novel tail with three low vertical stabilizers enabled use of existing hangars and provided sufficient vertical fin area to allow the aircraft to take off with only two engines on one side operating. The wing planform was similar to the DC-3, with a swept leading edge and almost straight trailing edge. The four 1,450 hp (1,080 kW) Pratt & Whitney R-2180-A Twin Hornet 14-cylinder radials were all mounted with noticeable toe-out, particularly the outer pair.

 

[facthunter]

Such a Plane would never be able to take off with Just two engines operating on one side. . Stall would be about 78 Knots and VMC(a) with two out about 103 kts. You'd need to rely on the steering to get to that speed to have directional control even while still on the ground.  Also only the inner engines have Hydraulic Pumps. I think it's HYPE.  Nev

[red750]

The above is a direct copy of the Wikipedia page. On another site, I found this:

 

It had a tail with 3 vertical stabilizers enabling use of existing hangars and to provide

sufficient fin-area to maintain flight on only 2 engines running at one side. Ceiling on

only 2 engines was 2440m.

 

There is a large amount of additional data on this website:

 

https://www.aircraftinvestigation.info/airplanes/Douglas_DC-4E.html

 

[facthunter]

Wikipedia has warnings about the accuracy of some of the Postings on their site. Your statement Had" TAKE OFF with only  2 engines on One side operating". Once Vmc (a) for 2 engines on one side out is reached and only then is the Aircraft controllable and then you have to have successfully Feathered the two affected Motors, got the gear and flaps  retracted  Plane trimmed up Fuel balance addressed. These Planes even on all engines need the earths curvature to climb when at AUW.  I trained with a Complete Idiot wo INSISTED on Failing the two engines on one RH side just at the Minimum Vmc for that engine and Today It would NEVER be allowed at such a low Height. I complained at the time and was told I would be sacked IF I didn't do it.. I have about 1900 Hours on a DC4 -C54.  The Controls are NOT Hydraulic Powered either, and are EXTREMELY heavy.  Hydraulics power Landing gear ext and retract, Nosewheel steering Brakes Cowl gills and autopilot servos.  Longest trip without Landing, Lae to Essendon . 12 hours flight time. Nev

[facthunter]

I got a security Warning on that Link. Nev

[BrendAn]

3 hours ago, facthunter said:

Wikipedia has warnings about the accuracy of some of the Postings on their site. Your statement Had" TAKE OFF with only  2 engines on One side operating". Once Vmc (a) for 2 engines on one side out is reached and only then is the Aircraft controllable and then you have to have successfully Feathered the two affected Motors, got the gear and flaps  retracted  Plane trimmed up Fuel balance addressed. These Planes even on all engines need the earths curvature to climb when at AUW.  I trained with a Complete Idiot wo INSISTED on Failing the two engines on one RH side just at the Minimum Vmc for that engine and Today It would NEVER be allowed at such a low Height. I complained at the time and was told I would be sacked IF I didn't do it.. I have about 1900 Hours on a DC4 -C54.  The Controls are NOT Hydraulic Powered either, and are EXTREMELY heavy.  Hydraulics power Landing gear ext and retract, Nosewheel steering Brakes Cowl gills and autopilot servos.  Longest trip without Landing, Lae to Essendon . 12 hours flight time. Nev

this is one of the best posts i have read on here. i can't even imagine what it would be like when he shut 2 engines down.

[facthunter]

Believe ME it's NOT a very Capable flying Machine when these failures happen. Later I experienced a Complete Hydraulic failure with the same dope. He didn't even spot the Quantity and Pressure in the Prelanding check. I had to say" Hey NO quantity and NO Pressure" HE just Blithely called the normal response. The destination was fogged in (Port Moresby) so we had to hold in a racetrack Pattern at a couple of thousand feet. But it got even worse after that. The clown just further  " lost it"  No I'm not writing a Book. I just wondered HOW HE had got to where HE was, A checkie on that type of aircraft. I actually felt sorry for Him, so poor was the Performance. It's a co-incidence that I brought this up at the Men's Shed Today. Others who had flown with him thought exactly the same way. Nev