New Aircraft Quiz #25

[Doug Robertson]

1. What was the Robertson "Water-Plane"?

2. Be specific about its construction. Monoplane? Biplane? Etc?

3. What year was it first operated?

4. How many did it seat?

5. What powered the "Water-Plane"?

6. Bonus for what exactly it was used for.

Modesty or clan embarrassment has prevented me from proffering this quiz earlier. Take your choice.

[moxy]

I'll have a stab at an aquaplane built by Milton and Russell Robertson. It was apparently a hull shaped like a sled with an outboard motor mounted on it. Possibly a 32hp Evinrude. The hull was attached via pivoting booms to a cockpit/fuselage type construction. When the contraption reached about 30 mph the front would rise to about 10 ft. Lateral control was provided by a rudder with elevator for vertical control.

It was built in 1930. I would love to see a picture of the thing but can't find any illustrations anywhere. There were only two built and I haven't a clue what they would have been used for.

Rob

[moxy]

I meant to add it had only one seat. I'm not surprised.

[Doug Robertson]

Rob,

You continue to amaze me. Before formulating this quiz, I found zip, nada on the Web about it. Here are the answers with some expansion as my source does have a photo of it in "flight", and I use that word advisedly.

1. The Robertson "Water-Plane" consisted of a ribbed cloth-covered wing with considerable dihedral and large chord appearing to be about 40 foot span attached to a framework supporting a flat-bottomed rectangular hull (in the nautical sense) with bow hull taper upon which the sole pilot was seated just forward of the wing with stick and engine controls. Two wood booms hinged below the wing's center extended aft about 20 feet to terminate on a smaller flat-bottomed rectangular hull with hinge points on the hull aft of the motive power. This aft hull was also tapered at the bow. (More on the motive power later).

2. The craft was a monoplane.

3. It first "flew", and I use the term advisedly, in 1930.

4. The pilot was sole occupant; most assuredly named Robertson.

5. Motive power was an outboard motor (water-propulsion type) fastened a bit forward of the hinged booms centered on the aft flat-bottomed surface-skimmer hull. My photo source suggests a 33 Horsepower Evinrude with exposed large flywheel and fuel tank behind curved to mate near the flywheel. (A friend had such an Evinrude motor in the 1940s in Minnesota we water-skied behind). The "Water-Plane was designed to traverse water courses only and not get completely airborne. My photo source does not show any air rudder nor any elevator of the aircraft kind-in other words-no tail surfaces at all.

6. I can only speculate, but suggest the purpose of the Robertson "Water-Plane' in the Great Depression Era was to terrify the pilot with a thrill ride diversion a few feet above the water. My source-quote-"Reflecting on it, one wonders if a good yank on "the stick" would tend to create the top half of an inside loop, and a thorough dunking, not to mention the surprise!" In retrospect, the "stick" might have controlled wing flaps for lift.

My source further compared it with an ice boat driven by an aircraft motor pusher propeller or a flat-bottomed air-boat driven by a shrouded airplane motor's pusher propeller for skimming in marshy swamps. Florida's Everglades comes to mind. I humbly apologize for calling this an aircraft quiz, and also apologize for not being able to enclose the photo of the contraption nor reveal its source. But, again, congratulations Rob for your diligence and getting it right.

[THoff]

Here is a video of it:

http://www.youtube.com/watch?v=oSgn6jvZnrM

[Doug Robertson]

Thanks Torsten for your great find. Check the fake registration early on in the film- NFLY. My sole photo in my source appears to be a reversal in direction flight in the same port waters. A demonstration may be better than an explanation, which presupposes certain aspects of operation.

I didn't know the Robertson water-craft received a patent. Things were simpler and easier back then. One of my U. S. Patents filed 22 September 1975 was not granted until 16 January 1979.

[moxy]

Your posers are certainly getting tough Doug.

Thank you for the extra information, I'm certainly learning a lot about what to an English bloke are fairly obscure American aircraft builders.

Torsten, I also thank you for putting the splendid film on here. What a fascinating clip. After watching it I can understand why I had never seen or heard of it over here.

Rob