WW2 bomber turret question

[Woy Wogers]

Did the turrets in WW2 bombers employ any mechanisms to prevent the gunners hitting their own aircraft?

Or did the gunners just have to watch out for their own engines / wings / tail etc.?

WW

[VX275]

In a word, Yes.

An obvious one to look at is the Lancaster Mid-upper, the fairing around its base provided what was called a taboo track which prevented the guns from hitting its own airframe. Other installations just positioned the turret such that the arc of fire wasn't intersected by the airframe. The true art was in positioning all the guns / turrets such that the arcs of fire intersected and didn't leave any gaps in the coverage.

[clarkieboy]

In addition to the above, a quick look at the B-24 Armament manual shows micro switches set to interrupt firing in both azimuth and elevation, to stop you hitting the tail fins and fuselage respectively from the top turret. Hope that's of some help.
Cheers
Iain

[Noyade]

mechanisms G'day Woy. Different turret manufacturers, different mechanisms I guess. Here's how Boulton Paul did it, using a circuit breaking insulated area on an interrupter drum.

The manual makes it quite clear though, "the guns must always be fired electrically, otherwise the purpose of the interrupter is defeated".

Which got me thinking, if they weren't fired electrically (disengaged?) then is it possible to do some damage to yourself? I understand that the turret was used in such aircraft as the Roc, Defiant and Hudson.

http://img253.imageshack.us/img253/7627/boultonpaul.jpg (http://img253.imageshack.us/i/boultonpaul.jpg/)

[Saab Dastard]

Woy Wogers

Interesting and timely thread - a few days ago I was watching some footage of a B-17 ball turret rotating and depressing very rapidly while both guns blazed away, and it got me wondering also about how the aircraft was protected from heat-of-the-moment over-exuberance by its own crew!

With the kind of mechanisms mentioned above, I guess the only guns that could inflict self-harm would be those such as the waist guns on the B-17 and B-24, where there was no obvious mechanism to prevent strikes on the wings and tailplane - or was there?

I have also come across several accounts of "friendly fire" from one bomber to another in the USAAF daylight box formations, but it was probably unavoidable, given the doctrine of close formation for massed fire support. Just one more thing for the crews to have to put up with.

SD

[avionic type]

If memory serves me right on my elect /mech air course in 1949 we were instructed on a modified system of the Bolton paul system where the outline of the tail section and astral blister at the front of the plane was marked on the drum shutting off the electrical supply to the guns, the Lanc had a Gun deflecting blister round the mid upper turret which did the same thing except I think it didn't cut the guns out. [why can't I remember what I had for lunch on monday?]:ugh::ugh::ugh:

[TerminalTrotter]

A different question. Were the power turrets movements 'proportional' control, as in the harder you push/twist the faster it goes, or were they on/off at a fixed rate.

TT

[avionic type]

The one for the mid upper on the Shackleton 1s was, perhaps someone can remember if it was electricly driven I recall there was an inverter just to the side of it and it was a pig to change, access to the bolts which held it down was limited or was it for the radio /radar?it was just aft of the galley, I can't remember any hydralics :confused::confused::confused:

[spitfire]

We recently got the ball turret working on EAA's B-17 and I took it for a spin... the controls were proportional... more input on the yoke, greater speed.

htt<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/5hfaSpLnta0&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/5hfaSpLnta0&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>p://www.youtube.com/watch?v=5hfaSpLnta0

[Saab Dastard]

That ball turret footage without the guns suddenly made me think of the one-man space pod from 2001, Space Odyssey. I wonder if Kubrick / Clarke had it in mind when the film was being made.

SD

[TerminalTrotter]

Thank you gentlemen, that's something I often wondered about. I had visions of the early radio control models, controlled in steps by going full rudder/no rudder, until they pointed in the desired direction.

TT

[Lancman]

The mid-upper turret in the Mk I Shack was a Bolton Paul B-17 all electric job. One of my favourite seats in the Shack, until the detachable section of the cupola detached itself in flight one day and left me sitting out in the fresh air.

[avionic type]

LANC An eye watering moment plus an underwear change ?thank for jogging the old memery box if it is allowed when and what was your squadron I was with 224 at Gib 51 to53 mine was in the nose as a flying spanner .not many years part us in age



It is most certainly allowed and I suspect that most of us would love to hear more stories from the both of you!

The Mods

[Double Zero]

Lancman's tale reminds me of an interesting experience Test Pilot Robin Milne had when working for Airspeed ( his life has so many tales, a lot only discovered after his passing, I can't repeat them here, but they included climbing the Eiger, ditching a Sopwith Camel in front of the carrier while fighting the Bolsheviks, being captured and escaping from the same, ' happening to be on holiday ' in 1938 Germany, etc; The Tartan Terror has more on his tribute site ).

Anway Robin ( Bob to everyone ) production tested over 2,000 Oxfords, among many other things.

When they came up with the MkII with mid upper turret, he flew it; fortunately unoccupied, as the thing blew off in mid flight !

He entered in his log book, " took off as MkII, landed as MkI ".

When he and an engineer went to fetch it - they had a good idea where it had come off and alerted the local police - they were immediately arrested as possible spies, spending hours in a cell before he could get his boss ( quite possibly Nevil Shute Norway, later to become the famous author ) to talk sense into the plods.

[Lancman]

By a strange co-incidence I've just been watching "No Highway in the Sky", the film adaptation of Neville Shute's "No Highway". He was, of course, not only a brilliant aircraft stress engineer but the founder of Airspeed Limited. One of the high points of the film is when Mr. Honey (James Stewart) retracts the Reindeer's undercarriage on the ground in order to stop it taking off. Which brings me to a slightly similar incident that I witnessed from a distance, I'm glad to say, a Shackleton accident at Kinloss.
Two experienced captains were being checked by a Training Captain and after a roller (crunch and go) they climbed ahead to change the pilot in the left hand seat. Now I must explain that the Shack undercarriage selector consisted of two buttons, push the top one in, the bottom one popped out and the undercarriage came up. And vice-versa. At the downwind point the captain under check called for undercarriage down and and the checker pushed the protruding button and called "Undercarriage down, two green lights". Unfortunately they'd forgotten to retract the undercarriage after the roller and you can guess the rest.
And I see that from a thread on the Rumours and News forum that distraction is still causing aircraft to land wheels up 55 years later.

[avionic type]

We had a similar accident at Gib on a training exercise of "circuits and bumps " ours came roaring down the runway, a mighty bang, a slithering of metal followed by a deathly silence ,the crew got out saying they had 2 greens and muggings who did the intermediate inspection and another electrician who did the D.I were told to get our storys right for the "Quart of Ink" but fortunatly we were never called as it was proved by removing the inspection panels over the wings which showed the uplocks were fully locked up , and the undercart was never selected down. The aircraft was repaired by a working party from AVROs I believe the pilots and the training Captain lost some years seniorority :{:{:{
Oh happy days

[Lancman]

Sorry for the thread drift chaps.
Avionics type - I've pm'd you.

[Double Zero]

Lancman,

You've probably read it already, but Nevil Shute's semi-autobiography ' Slide Rule ' is a must.

Speaking of turrets etc and interruptor gear, I have been in B-17 'Sally B' in 'Memphis Belle' mode at the time, sadly only on the ground.

The waist guns were just supported by shockcords, but as they were fake guns anyway, the real thing may have been different, or one could easily shoot one's own wing ?

DZ