BIG Prop-Jobs!

[Mossie]

Recentley on the way to work, there have been some monstrous propellor blades waiting in holding yard at the docks, destined to be mounted onto several wind turbines.  Which, in a whiffers mind set, got me thinking, think of the size of the aircraft that those props could power!!!

In turn, that got me thinking about the whiffability of big propellor driven aircraft.  With a few exceptions, big propellor aircraft tend to be built in small numbers & with relatively few operators, leaving the door wide open.  So, TWA Spruce Goose?  BOAC Saro Princess or Bristol Brabazon?  Indian An-22 (sorry can't resist it!) big Cock?  RCAF Short Belfast?  RAF B-36?

[deathjester]

I think that aircraft for such huge props would have to be a Hybrid Air Vehicle-otherwise there wouldn't be a runway in the world large enough for it.  Or the SHIELD Helicarrier!  That's supposed to have similar [large, silent] props.

[kitnut617]

Well the Flying Pancakes had huge props which look a little like those windmill props Simon, then more recently we have the V-22 

[Jennings]

Driving to and from work on Interstate 81 in southwest Virginia, I frequently see over-long tandem trailers carrying individual wind turbine blades.  The round base of the blade roots are probably on the order of 10 feet in diameter, and the blades are at least 75' long (probably more).  I've never seen more than one blade mounted on a truck at a time.  Figuring the turbine would have at least two, if not three of these blades, that's got to be one heck of a big wind turbine.  Not sure where they're going, but if you mounted something that big on something like a big dirigible, you could make some headway!

J

[Daryl J.]

Pass the idea on to Hayao Miyazaki and it wouldn't be at all surprising to see something in Japanimation featuring just such an aircraft.   He's nuts about flying machines and regularly uses them in his works.    Witness the (cut) scene with Porco Rosso flying the 3rd version of the Savoia featuring a turboprop as it passes a French Caravelle jet.   Ha!



Daryl J., thinking these huge props could be used for some balloon based wind farm.

[John Howling Mouse]

Silly humans....you can't harvest energy from the wind-----you need good ol' all-natural petroleum for that!   

Don't know if your topic originally intended to discuss oversized props on aircraft or just large aircraft that happen to be prop-driven.

If it was the former: would the oversized prop design by necessity involve a tilt-rotor effect (we've had some interesting concepts on the site for tilt-rotors mounted on other aircraft)  or are there other ways to mount oversized props I just haven't thought of yet (other than autogyro or Rotodyne-style scenarios)?

[B777LR]

How to: Make the biggest heavier than air flying object:
Ingredients: 1x Planet, a few million modified windmills (generator can propel the prop, instead of being propelled), lots of batteries.

1. Take planet
2. Fit all the windmills along equator, about 150 meters apart.
3. Issue each windmill with a bunch of batteries (like WWII U-boat batteries)
4. Let windmills recharge batteries to full
5. When full, let the windmills run full power, all pointing towards the south!

[jcf]

The largest wooden prop ever used on an aircraft was the 6.9m(22' 7.5") prop fitted to the Linke-Hoffman RII four-engine bomber of WWI. The four engines were connected by a geartrain to drive the single prop at 545rpm. The aircraft looked like a huge single-engined aircraft.

Wingspan: upper 42.16m (138' 4"); lower 33.96m (11' 5")
Length: 20.32m (66' 8")

I'll post photos, drawings and more data later.

Jon

[Mossie]

Silly humans....you can't harvest energy from the wind-----you need good ol' all-natural petroleum for that!   

Don't know if your topic originally intended to discuss oversized props on aircraft or just large aircraft that happen to be prop-driven.

If it was the former: would the oversized prop design by necessity involve a tilt-rotor effect (we've had some interesting concepts on the site for tilt-rotors mounted on other aircraft)  or are there other ways to mount oversized props I just haven't thought of yet (other than autogyro or Rotodyne-style scenarios)?

Both really Baz, thought they'd be some pick up on large prop aircraft but I'll go with the flow!  I guess you could mount the prop/engine on some kind of pylon lofting it above the aircraft.  More practically, you could put large props on a high winged aircraft, mounting the engines over the wings & a gull wing would further faciltate that, something along the lines of a land based Be-12.  Stalky landing gear would hep too.

[Madoc]

Daryl,

Witness the (cut) scene with Porco Rosso flying the 3rd version of the Savoia featuring a turboprop as it passes a French Caravelle jet.

Huh?  Where was this?  I'd love to see that!

Madoc

[RLBH]

There was once a proposal for a nuclear turboprop to power a blimp, using a suitably-modified UH-1 rotor as the propeller...

[jcf]

Linke-Hoffman R.II Part 1

The main gear wheels are five feet in diameter.

Jon

[jcf]

Linke-Hoffman R.II Part 2

The engines are four 260hp D-B.

It was planned to add a Brown-Boveri supercharger on the production version of the bomber.
A 12-passenger civil airliner version was also schemed.

Jon

[kitnut617]

When you see all the multi engined tractors at the tractor pulls, it's really all 'old hat' isn't it?

[Sentinel Chicken]

You sure as hell wouldn't want this to happen, then: http://www.liveleak.com/view?i=8be_1203819244&p=1