Boulton Paul Defiant

Started by apophenia, March 11, 2010, 01:46:08 PM

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NARSES2

Quote from: Mossie on December 22, 2010, 01:47:40 PM
I'm guessing here, but I would think that as the number of prop blades increased as the war progressed, this would make it more difficult for interrupter gear? 

Perhaps surprisingly Mossie there's a couple of WWI aircraft with synchronised mg's and 4 bladed props. RE8 and Siemens Schukert D.IV off the top of my head
Do not condemn the judgement of another because it differs from your own. You may both be wrong.

rickshaw

I think its a combination of higher RPM and more blades that caused a problem for synchronised MGs.  As RPM of the prop started approaching the RPM of the machine gun, something wasn't going to work very well...  ;)
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kitnut617

#47
I think though Rick, that as aircraft started flying at 400 mph and faster, the prop speed was actually slowed.  From what I've read this was about 2000 rpm but on some it was 2500 rpm.  The problem of having the rpm to high is you run into the blade tips going supersonic.  On a Tempest for instance with a prop of almost 14'-0" diameter there was a very real chance of the tips going supersonic, the blade tips moving at 1466 feet per second and that was when it was standing still on the tarmac with the engine being run up.  Add another 450 mph to that and you have a problem with supersonic tips.  And of course as you went higher in altitude, that compounded the problem.

When I went to Reno to watch the air racing some years ago, I was quite surprised at how slow the props turned on the Unlimited Class racers and the sound was something else.  Not so in the T-6 Texan/Harvard class where they're not allowed much in modifications, you could soon hear when they had reach their maximum speed, the racket from the blade tips as they approach supersonic speed was terrible (anyone who's seen a Harvard in a dive would understand what I'm talking about)
If I'm not building models, I'm out riding my dirtbike

PR19_Kit

Quote from: kitnut617 on December 23, 2010, 06:52:20 AM
.....(anyone who's seen a Harvard in a dive would understand what I'm talking about)

Try flying in one! OUCH!  :banghead:
Kit's Rule 1 ) Any aircraft can be improved by fitting longer wings, and/or a longer fuselage
Kit's Rule 2) The backstory can always be changed to suit the model

...and I'm not a closeted 'Take That' fan, I'm a REAL fan! :)

Regards
Kit

sequoiaranger

#49
>[rickshaw]:I've been thinking, "longer wings..." and all that.  How about a high-altitude Defiant for intercepting Ju86Ps over the UK?  Might need a new engine as well as the longer wings but those turret guns would be a killer against the unarmed Ju86Ps.<

Careful---those high-flying Ju-86P's aren't as helpless as they might seem--they will have my "He-121 Stratsospheric Fighter" (W.I.P.) to protect them. Watch out! The same ol' "hit 'em from the front and below" might apply to your Defiant, and at that altitude there is more room to approach from underneath!!
My mind is like a compost heap: both "fertile" and "rotten"!

jcf

The answer to the synchronization 'problem' is the same one the Germans used, electrically ignited primers.

rickshaw

Quote from: sequoiaranger on December 23, 2010, 09:14:11 AM
>[rickshaw]:I've been thinking, "longer wings..." and all that.  How about a high-altitude Defiant for intercepting Ju86Ps over the UK?  Might need a new engine as well as the longer wings but those turret guns would be a killer against the unarmed Ju86Ps.<

Careful---those high-flying Ju-86P's aren't as helpless as they might seem--they will have my "He-121 Stratsospheric Fighter" (W.I.P.) to protect them. Watch out! The same ol' "hit 'em from the front and below" might apply to your Defiant, and at that altitude there is more room to approach from underneath!!

Ah, but your He121 won't be there the first or second time it happens.  Defiants as "Air Dominance" fighters!  [insert evil laughter]...   ;D ;D ;D

Anyway, plenty of room in the longer wings for the 12 MGs Defiants are reputed to have carried!   ;D ;D :o
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

pyro-manic

Hmmm, I like the Schrage-musik idea! I recently acquired a Defiant kit, and that might well be how it ends up. :thumbsup:
Some of my models can be found on my Flickr album >>>HERE<<<

rickshaw

Quote from: apophenia on December 24, 2010, 02:58:57 PM
High-altitude Defiant conversion.

Like that one.  Mmm, tempting, tempting...  :thumbsup:
How to reduce carbon emissions - Tip #1 - Walk to the Bar for drinks.

sideshowbob9

Love the Schräge Musik idea!  :thumbsup:

GTX

I'm toying with the idea of a RN FAA carrier based version - say the Roc was beaten by a Boulton Paul Sea Defiant with folding wings and at least a couple of forward firing MGs.

Regards,

Greg
All hail the God of Frustration!!!

pyro-manic

Put the guns outboard of the folds - Two or three per wing, for 4 or 6 forward-firing .303s. Another option could be a pair of cowling-mounted synchronised guns?
Some of my models can be found on my Flickr album >>>HERE<<<

GTX

#57
I was thinking of 2 MGs in each outer wing.  Hadn't really gotten to the details yet though - anyone have a good cutaway drawing that I can refer to?

regards,

Greg
All hail the God of Frustration!!!

GTX

The attached drawing (courtesy of Justo Miranda) might help re the placement of wing MGs for the Defiant.

I am thinking of replacing the outer wing tank with a pair of MGs and adding a couple of drop tanks (probably similar to those from the Hurricane) to help make up the lost fuel.



Regards,

Greg
All hail the God of Frustration!!!

GTX

Some more inspiration for the Defiant - also from Justo:









Regards,

Greg
All hail the God of Frustration!!!