Contra-rotating props...

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TheGreenGoblin
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Contra-rotating props...

#1 Post by TheGreenGoblin » Fri Oct 09, 2020 10:51 am

A bit of nostalgia but also some comments on the efficiency (or lack of it) inherent in contra-rotating designs.

I love Soviet era designs. Old fashioned, noisy and yet still totally fascinating.

This Ukrainian crew just fill one with quiet confidence that they could take that big bird anywhere.

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Re: Contra-rotating props...

#2 Post by TheGreenGoblin » Fri Oct 09, 2020 11:17 am

Some advantages of a contrarotating prop...

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Re: Contra-rotating props...

#3 Post by TheGreenGoblin » Fri Oct 09, 2020 11:21 am

An excuse to look at the Fairey Gannet...



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Re: Contrarotating props...

#4 Post by CremeEgg » Fri Oct 09, 2020 11:25 am

Having been woken by an An12 at 0300Z droning over southern England at FL260 on its way to Madrid and just a few minutes ago an RAF A400M droning across eastwards at FL310 - this seems a remarkably apt thread. The A400M noise is a pet hate of mine and although not contra=rotating props in the Shackleton/Gannet style it still has contra-rotating props in that number 1 rotates anti-clockwise when viewed from the front but No 2 is clockwise; then No 3 is anti-clockwise and No 4 is clockwise. I'm sure Mr Giggle could answer my questions but I wonder if this has an effect on its noise or if it's just the propellors design. Anyone with any ideas? I'm sure Fox would know!

GG - must study the videos you posted whilst I was typing.
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Re: Contrarotating props...

#5 Post by TheGreenGoblin » Fri Oct 09, 2020 11:28 am

CremeEgg wrote: ↑
Fri Oct 09, 2020 11:25 am
 Having been woken by an An12 at 0300Z droning over southern England at FL260 on its way to Madrid and just a few minutes ago an RAF A400M droning across eastwards at FL310 - this seems a remarkably apt thread. The A400M noise is a pet hate of mine and although not contra=rotating props in the Shackleton/Gannet style it still has contra-rotating props in that number 1 rotates anti-clockwise when viewed from the front but No 2 is clockwise; then No 3 is anti-clockwise and No 4 is clockwise. I'm sure Mr Giggle could answer my questions but I wonder if this has an effect on its noise or if it's just the propellors design. Anyone with any ideas? I'm sure Fox would know!

GG - must study the videos you posted whilst I was typing.
Your interesting comment on the TRABB thread spurred me on CremeEgg... :-bd
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Re: Contra-rotating props...

#6 Post by Boac » Fri Oct 09, 2020 11:30 am

In post#1 TGG wrote:This Ukrainian crew just fill one with quiet confidence that they could take that big bird anywhere.
It'll be fine when the Flt Eng comes round from the Vodka =))
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Re: Contra-rotating props...

#7 Post by bob2s » Fri Oct 09, 2020 10:53 pm

Bo, ifthat was the case then this must be the result of an overnight stop.

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Re: Contra-rotating props...

#8 Post by TheGreenGoblin » Sat Oct 10, 2020 4:59 pm

Looking at those folks above I would suggest they are more like contra rotating poeps... :)

Here is something more edifying...


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Re: Contra-rotating props...

#9 Post by Pontius Navigator » Sat Oct 10, 2020 5:02 pm

Was the Gannet unique?
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Re: Contra-rotating props...

#10 Post by TheGreenGoblin » Sat Oct 10, 2020 5:08 pm

Pontius Navigator wrote: ↑
Sat Oct 10, 2020 5:02 pm
 Was the Gannet unique?
In what sense do you mean Pontius?
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Re: Contra-rotating props...

#11 Post by Pontius Navigator » Sat Oct 10, 2020 5:10 pm

Two engined contra
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Re: Contra-rotating props...

#12 Post by TheGreenGoblin » Sat Oct 10, 2020 5:16 pm

Pontius Navigator wrote: ↑
Sat Oct 10, 2020 5:10 pm
 Two engined contra
Ah yes and I suspect it is unique.

Hang on I can think of another...


https://en.m.wikipedia.org/wiki/Bugatti_Model_100

Sadly the restored Bugatti killed it's pilot.
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Re: Contra-rotating props...

#13 Post by k3k3 » Sat Oct 10, 2020 5:26 pm

The Brabazon had a similar arrangement four times over, it was powered by an arrangement of eight Bristol Centaurus radial engines which drove a total of eight paired contra-rotating propellers set on four forward-facing nacelles.
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Re: Contra-rotating props...

#14 Post by G-CPTN » Sat Oct 10, 2020 5:30 pm

There was a Blackburn B88 'predecessor' which was discontinued in favour of the Gannet.
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Re: Contra-rotating props...

#15 Post by TheGreenGoblin » Sat Oct 10, 2020 5:31 pm

k3k3 wrote: ↑
Sat Oct 10, 2020 5:26 pm
 The Brabazon had a similar arrangement four times over, it was powered by an arrangement of eight Bristol Centaurus radial engines which drove a total of eight paired contra-rotating propellers set on four forward-facing nacelles.
What an extraordinary aircraft.
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Re: Contra-rotating props...

#16 Post by TheGreenGoblin » Sat Oct 10, 2020 5:34 pm

https://en.m.wikipedia.org/wiki/Arsenal_VB_10
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Re: Contra-rotating props...

#17 Post by TheGreenGoblin » Sat Oct 10, 2020 5:35 pm

https://en.m.wikipedia.org/wiki/Arsenal_VB_10
The Arsenal VB 10 was a French fighter aircraft developed during and shortly after World War II. It was a low-wing monoplane with retractable tailwheel undercarriage and of largely orthodox configuration. The ultimate product of a design that began with the Arsenal VG 10 prior to the war, the VB 10 added a second engine behind the cockpit which drove a second propeller, coaxial with and contra-rotating to the propeller driven by the engine in the nose.
arsenal-vb-10-c-1-production.jpg
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Re: Contra-rotating props...

#18 Post by G-CPTN » Sat Oct 10, 2020 5:37 pm

I was a youngster when I watched the Brabazon land at Filton.
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Re: Contra-rotating props...

#19 Post by ian16th » Sat Oct 10, 2020 6:06 pm

Westland Wyvern

As far as I know, still the worlds only turboprop 'fighter'.

I once re-fuelled one at Istres.
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Re: Contra-rotating props...

#20 Post by TheGreenGoblin » Sat Oct 10, 2020 6:12 pm

Would have been an extraordinary aircraft...the Boeing Pelican Ultra...
Boeing Pelican.JPG
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https://www.boeing.com/news/frontiers/a ... /i_pw.html

https://en.wikipedia.org/wiki/Boeing_Pelican
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