Calling all aircraft mechanics and flight engineers

[Flying Trucker]

Goodly afternoon all...

I posted this here rather than in the Real Aviation Forum as I believe it can go in either.   :)

Here is my idea of the alternative:

http://www.basicaircraft.com/turbo-alte ... bpe-14.asp

Now I was at one of the local bugsmasher fields today and some of the old retired rocking chair flying geezers were discussing the difference between these.
(a)  Slipstream Wind Generator
(b)  Propeller Wind Generator
Are they the same?

My thoughts are this.

A propeller wind generator is located on the leading edge of a wing or forward strut with the propeller facing the direction of flight.
A propeller wind generator dates back to the First World War 1914 to 1918 and was used to power the radios in Observation and Comunications Aircraft.
The propeller wind generator worked well when the aircraft was in cruise flight.

I believe the slipstream wind generator was located on older aircraft just behind and below the propeller and mounted to the main gear strut bracing.
On more modern aircraft I believe the slipstream wind generator was automatically deployed somewhere along the bottom of the fuselage when the aircraft lost all engine power.

I could not find pictures or links to post to back up my idea of what the difference is so if anyone would like to add to this I look forward to your opinions.   ;)

Cheers...Happy Landings...Doug

[Hagar]

I believe the slipstream wind generator was located on older aircraft just behind and below the propeller and mounted to the main gear strut bracing.

We used to call these wind-driven generators. My company used to overhaul them but parts are difficult to come by these days. They were used on many British-built light aircraft where engine-driven generators could not be fitted, for example the Gipsy engines on the DH Moths have no provision for a generator. I've seen them fitted in various locations & not always behind the prop.*

The Turbo Alternator from your link is the modern version & used for the same purpose. They're much lighter & more efficient than the old generators. I believe the small propellers fitted to WWI aircraft like the Sopwith Pup were generally used to drive a fuel pump.

On more modern aircraft I believe the slipstream wind generator was automatically deployed somewhere along the bottom of the fuselage when the aircraft lost all engine power.

This would be the RAT (Ram Air Turbine) fitted to modern jet airliners. http://www.aerospaceweb.org/question/electronics/q0044c.shtml

*PS. I should have some photos somewhere. I'll look them out when I have a moment.

[Flying Trucker]

Hi Doug...

Thanks for the link Doug, never had those gadgets on anything I flew.   ;D

Found this link..."Ron's Follow-up" half way down the page, cute story and good picture of the piece of equipment.

[Hagar]

Interesting link Doug. Not many light aircraft had much use for electricity when I first worked at Shoreham in the early 60s. Our Tiger Moths were not fitted with starter motors, radio or any of those fancy gadgets. No heater either. The instructor conversed with the pupil over the Gosport Tube. Our brand-new Beagle Terrier was a little more modern & had a stall warning horn powered by dry torch batteries. I see a lot of them fitted with wind-driven generators these days

I found a few photos showing the location of these things. This is the best I can do at short notice.

This is the typical Auster installation.



DH Hornet Moth. Note the generator is outside the propeller arc.


Rearwin Cloudster. This is a popular location.


The Sopwith Pup wind-driven fuel pump on the front centre-section strut.

[Flying Trucker]

Wow wonderful shots Doug...very nice...

They certainly show the two locations I was talking about and a few more.

I do not think folks realize just how far aviation progressed during the First World War years and again the advances during World War Two.

[TacitBlue]

After what Hagar said, I don't really have anything to add other than that I've also heard wind powered generators called "ram-air alternators". That is at least for the type that are alternators rather than generators. Interesting subject, and nice photos Hagar. 8-)

[Flying Trucker]

Hi TacitBlue...

Yes I do believe there are several types on the market.


http://www.basicaircraft.com/product-reviews.asp

I do believe some of this equipment should be standard equipment on all aircraft.

Cheers...Happy Landings...Doug

[beaky]

The nice thing about the prop-driven ones is that they start turning, and providing electricity, as soon as the engine is started. The slipstream or ram-driven types require the plane to be moving (and pretty briskly).

The 1946 Aeronca Champ I flew in California had a prop-driven generator mounted between the mains, to provide power for only the comm radio (no other electronics and no lights of any kind). I could get the ATIS before even propping the plane, knowing that as soon as I coaxed the old A-65 to life, the generator would start recharging the small battery. And of course there was no worry about battery life when using the radio while taxiing.

Not sure of the manufacturer or when it was added (didn't come with a generator, or a radio, from Aeronca), but it was perfect for providing the minimum comms needed to operate from a Class D airport.
My friend John has a 1940  Aeronca L3 that has a similar setup- he needs it mostly because at 47N, he needs to have a Mode C transponder, although a comm radio is not required (he does have a radio, too, though). These planes were manufactured long before there was any airspace requirements for transponders or radios. You could putt-putt your little Cub or Champ into Newark Airport before WWII using only light-gun signals from the tower (if that). But today's US airspaces require owners based at many airports to occasionally force these blasphemous additions on their antique birds.

The only drawback, as would be the case with a wing-mounted "windmill"

[Hagar]

The nice thing about the prop-driven ones is that they start turning, and providing electricity, as soon as the engine is started. The slipstream or ram-driven types require the plane to be moving (and pretty briskly).

The 1946 Aeronca Champ I flew in California had a prop-driven generator mounted between the mains, to provide power for only the comm radio (no other electronics and no lights of any kind). I could get the ATIS before even propping the plane, knowing that as soon as I coaxed the old A-65 to life, the generator would start recharging the small battery. And of course there was no worry about battery life when using the radio while taxiing.

That's a very good point although I've noticed that most of these 'prop-driven' installations remain stationary below a certain prop RPM. (This is more from the point of view of a photographer than engineer as it's nice to get a blur on that little prop.)

[beaky]

The nice thing about the prop-driven ones is that they start turning, and providing electricity, as soon as the engine is started. The slipstream or ram-driven types require the plane to be moving (and pretty briskly).

The 1946 Aeronca Champ I flew in California had a prop-driven generator mounted between the mains, to provide power for only the comm radio (no other electronics and no lights of any kind). I could get the ATIS before even propping the plane, knowing that as soon as I coaxed the old A-65 to life, the generator would start recharging the small battery. And of course there was no worry about battery life when using the radio while taxiing.

That's a very good point although I've noticed that most of these 'prop-driven' installations remain stationary below a certain prop RPM. (This is more from the point of view of a photographer than engineer as it's nice to get a blur on that little prop.)