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Thread: Lysander Grip

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    Lysander Grip

    This grip seems to have firing button similar to the Spitfire arrangement but the Lysander only hasw two 303.s can anyone explain the function of the button?
    Last edited by Graham Adlam; 10th October 2011 at 17:31.
    when you have excluded the impossible whatever remains however improbable must be the truth
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    That confused me to Graham. Turns out some Lysanders were fitted with a pair of 20mm Hispanos where the little stub wings should be. Made the Lysander with a tail turret look like an elegant piece of design. facts aplenty on the Spade Grip thread.

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    Quote Originally Posted by ian_ View Post
    That confused me to Graham. Turns out some Lysanders were fitted with a pair of 20mm Hispanos where the little stub wings should be. Made the Lysander with a tail turret look like an elegant piece of design. facts aplenty on the Spade Grip thread.
    Thanks for that.
    20mm cannon on a Lysander that sounds scary must have shaken it to bits when fired Seems a strange idea to fit fire power like this to an aircraft that clearly had little chance of catching let alone shooting down an EA. Also there seems little point for ground attack when you have aircraft like the Typhoon available. Cannon must have been allot of added weight to an aircraft designed to sneak in and out of Enemy territory on a short take off and landing, makes no sence to me.
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    Hi Graham,

    The Lysander was designed as an army co-op aircraft, so anything that could add to it's punch would come in handy for strafing. This was well before other canon armed types, eg. Typhoon Ib, Hurri IIc etc, were available.

    The ability to operate from short, rough strips was so that it could operate close to the front lines, and it just so happenned that it came in handy for 'spy dropping'.

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    Thanks for that seems it was pretty advance technology if it pre dated Tiffy and Hurricane ground attack aircraft.

    I dont suppose anyone has a picture of a Lysander with cannons?
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    Here you go Graham, not the best quality I'm afraid but illustrates the basics of the installation.

    http://img27.imageshack.us/i/300lys3.jpg/

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    I've just been delving into various books, including James Kightly's excellent Lysander book for a bit more detail on the cannon, and it seems that at least one squadron was supplied with cannon before the Battle of France, although they were never supplied with any 20mm ammo! A number of Lizzies were also fitted with 20mm during the Battle of Britain period as an anti-tank/anti-invasion barge measure, and this time they presumably had some ammo?!

    The fitting of 20mm seems to have been rather sporadic, although the installation is mentioned in the type's pilots notes. It seems many Lysanders had provision for the fitting of cannon, even if they weren't actually fitted.

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    Quote Originally Posted by AdlerTag View Post
    Here you go Graham, not the best quality I'm afraid but illustrates the basics of the installation.

    http://img27.imageshack.us/i/300lys3.jpg/
    WOW thanks for that, they just strapped them on the thing must have shaken like crazy when they fired. Would have thought it caused stability problems must have made the nose dip.
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    There were all sorts of lash ups made to counter Operation Sealion. How about Tiger Moths with bomb racks. Anything to frighten the horses which the Germans proposed to carry across the channel on their river barges. It is a great pity they never attempted this mad scheme.

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    Graham, you've sent me a pm but I cannot reply until you clear out your inbox. Laterz.
    The garage that keeps on giving

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    Quote Originally Posted by Air Ministry View Post
    Graham, you've sent me a pm but I cannot reply until you clear out your inbox. Laterz.
    done
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    Quote Originally Posted by PeterVerney View Post
    There were all sorts of lash ups made to counter Operation Sealion. How about Tiger Moths with bomb racks. Anything to frighten the horses which the Germans proposed to carry across the channel on their river barges. It is a great pity they never attempted this mad scheme.
    I actually have a 1940 piece of a Bomb rack for a Tiger Moth its a beautiful brass gadget.
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    Here's another photo. It looks to be K6127 which as listed as one of two prototypes delivered between July 37 and April 38. It must have almost stopped it when they were fired. Was there an eight gun Master, as well as snooker balls in socks and welded pikes to hold back the Hun.
    Last edited by ian_; 29th July 2010 at 15:59.

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    Quote Originally Posted by ian_ View Post
    Here's another photo. It looks to be K6127 which as listed as one of two prototypes delivered between July 37 and April 38. It must have almost stopped it when they were fired. Was there an eight gun Master, as well as snooker balls in socks and welded pikes to hold back the Hun.
    Stopped and nosed dived, Would think its highly unlikely it would have got a shot off at the invasion barges with swarms of BF 109s around. Its stange the humble Lysander had Cannons fitted long before the Hurricane and Spitfire, its got to be one of the best bodges the RAF came up with.
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    Was it the RAF's first cannon armed plane?

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    Quote Originally Posted by ian_ View Post
    Was it the RAF's first cannon armed plane?
    Cannot think of another, after all what other RAF aircraft was cable of mounting cannon at that time?
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    Hi
    Not sure, would have to check the book, but think the 500 Sqn anson's had the 20mm first.
    cheers
    Jerry

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    Quote Originally Posted by AdlerTag View Post
    I've just been delving into various books, including James Kightly's excellent Lysander book for a bit more detail on the cannon,
    Thanks!

    Quote Originally Posted by Graham Adlam View Post
    WOW thanks for that, they just strapped them on the thing must have shaken like crazy when they fired. Would have thought it caused stability problems must have made the nose dip.
    Why would it? Newton's third law applies; "To every action there is an equal and opposite reaction." Equal being the critical part. The Lysander was a reasonably large single-engine aircraft, with significant mass, similar to that of most cannon-armed single seat fighters of the time. For some reason, as soon as cannon are mentioned in non-fighter types, people seem to assume that on firing it would drop it out of the sky, despite the fact that a projectile would have to be fired a lot faster or be a lot heavier than most guns were capable of at the time. Vibration from firing was a different issue, and did cause problems on types like the Tetse Mozzie and the cannon armed B-25 at servicing, but the myths of 'stopping in mid air' are just hyperbole.
    Quote Originally Posted by PeterVerney View Post
    There were all sorts of lash ups made to counter Operation Sealion. How about Tiger Moths with bomb racks. Anything to frighten the horses which the Germans proposed to carry across the channel on their river barges. It is a great pity they never attempted this mad scheme.
    Just to be clear - it was a bit more than a 'lash up' and was devised before the risk of an invasion occurred.
    Quote Originally Posted by ian_ View Post
    Was it the RAF's first cannon armed plane?
    They probably had a SPAD or two in service in April 1918.

    Certainly there were the COW armed fighters and flying boat in the 1930s.

    By 1940 cannon were a reasonably widely used option in fighters and a few bombers if you consider the scene worldwide. Machine-gun only armament was still widespread, but certainly in the process of being supplanted.

    Regards,
    James K

    Looking and thinking...
    Vintage Aero Writer: Blog & Details

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    Quote Originally Posted by JDK View Post
    Thanks!


    Why would it? Newton's third law applies; "To every action there is an equal and opposite reaction." Equal being the critical part. The Lysander was a reasonably large single-engine aircraft, with significant mass, similar to that of most cannon-armed single seat fighters of the time. For some reason, as soon as cannon are mentioned in non-fighter types, people seem to assume that on firing it would drop it out of the sky, despite the fact that a projectile would have to be fired a lot faster or be a lot heavier than most guns were capable of at the time. Vibration from firing was a different issue, and did cause problems on types like the Tetse Mozzie and the cannon armed B-25 at servicing, but the myths of 'stopping in mid air' are just hyperbole.

    Just to be clear - it was a bit more than a 'lash up' and was devised before the risk of an invasion occurred.

    They probably had a SPAD or two in service in April 1918.

    Certainly there were the COW armed fighters and flying boat in the 1930s.

    By 1940 cannon were a reasonably widely used option in fighters and a few bombers if you consider the scene worldwide. Machine-gun only armament was still widespread, but certainly in the process of being supplanted.

    Regards,

    I would have to do some serious maths to work out the exact forces involved but the weight of the shot combined with the velocity it leaves the barrel would create quite a force pushing backwards on the legs.
    When you consider the positioning of the guns on the legs it would have an increased effect on stability a bit like a spanner turning a nut.
    I know from using flight sims that firing cannons do slow Spitfires down which is a heavier and more powerful aircraft than a Lysander so there is a considerable force invoked.
    It seems to me that some effect would be felt on the stick of a Lysander how much that effect would be would like i say take some working out, however at the very least it would affect sighting of the guns.
    It certainly caused some problems as they were not adopted operationally.
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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    Quote Originally Posted by Graham Adlam View Post
    I would have to do some serious maths to work out the exact forces involved but the weight of the shot combined with the velocity it leaves the barrel would create quite a force pushing backwards on the legs.
    When you consider the positioning of the guns on the legs it would have an increased effect on stability a bit like a spanner turning a nut.
    I know from using flight sims that firing cannons do slow Spitfires down which is a heavier and more powerful aircraft than a Lysander so there is a considerable force invoked.
    It seems to me that some effect would be felt on the stick of a Lysander how much that effect would be would like i say take some working out, however at the very least it would affect sighting of the guns.
    It certainly caused some problems as they were not adopted operationally.
    They are not particularly big rounds and the effect is very much short term, it would be no worse at effect on the aircraft handling qualities than mild chop......you may get one or two degrees pitch change on a prolonged burst but I seriously doubt it would be anymore.....now a Mollins gun would be a different story!!

    Regarding sims, I would not get too wound up on their accuracy if I was you....the whole thing with a gaming sim is to provide cueing that you are doing something. These sims are not always based on the best control and flight aerodynamics laws.

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    I've got this terrible feeling of deja vu.

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    Hi Graham,
    Entertainment flight sims are not a useful guide to real aircraft data, much as lots of effort is put into them these days. As Rocketeer's touched on, they are not there as an accurate performance simulacrum or a technical 'model' for the real thing.

    The 'effect of firing a cannon' issue is an emotional one rather than an understanding of the equations of force - do run the maths, by all means! On this I defer to those who are knowledgeable on such guns like Tony Williams who very generously advised me regarding a couple of armament questions on my Lysander book.
    http://www.quarry.nildram.co.uk/
    Quote Originally Posted by Graham Adlam View Post
    It certainly caused some problems as they were not adopted operationally.
    The issues weren't if the guns worked, it was getting it all organised for a useful task that was the issue - unless you've got documentation that says otherwise. The times they were attempted to be deployed logistics (France) plus other issues (Sealion) meant they were not brought into action, not because it didn't work.

    Regards,
    James K

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    Vintage Aero Writer: Blog & Details

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    Referring to Wallace Clarkes's 'British Aircraft Armament Vol2' the issue of the guns working was a very real one. The French Hispano canon procured for the RAF in 1938 were hand made and functioned well. The licence built British versions were prone to breaking and stoppages and the problems were not ironed out until 1940. Their mounting in Spitfire Ibs(?) caused quite a few problems in the Battle of Britain, with stoppages I think (can't put my hand on proof for that one though). That said the Lysander mounting does look spindly.

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    A very interesting thread 20mm armed Lsysander, didnt know they existed.
    Just for interest, if you have a recording of Charles Gardiner's Convoy attack and Dogfight 14/7/40 it's worth a listen to. Possibly recorded was the first time a 20mm cannon was used in combat by Spitfires.
    From memory the cannon armed Spitfire chased a German plane back to France and had a go at it, read somewhere that his guns jammed and he pulled away. This incident was described by Gardiner, who said that he had shot it down on the recording.
    G.

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    Quote Originally Posted by JDK View Post
    ...do run the maths, by all means!
    ...can’t resist a go at that! :diablo:

    Two Hispano-Suiza 20mm cannon firing 60 rounds each of AP-T, weighing 168g, at a muzzle velocity of 880m/s (in about 5 seconds)...

    ...one Westland Lysander with an empty weight of say 2000kg (assumed to be standing still in mid-air for ease of calculation).

    If the Lysander fired all 120 rounds the total momentum of the cannon ammunition would be:

    120 x 0.168 x 880 = 17,741 kgm/s

    If all that momentum is absorbed by the Lysander airframe (excluding blah, blah, blah):

    17,741 kgm/s = 2000 kg x V m/s

    V = 8.87 m/s

    V = 19.85 miles-per-hour

    So a stationary (empty) Lysander will be moving backwards at about 20mph by the time the cannon ammunition is exhausted...

    ...so a moving Lysander will lose about 20mph when the cannons fire (all their ammunition).

    A Lysander at maximum take-off weight (2877kg) will only lose about 14mph from its speed.

    (Awaiting somebody to spot a ‘school-boy-error’! )
    WA$.

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    Impressive and interesting figures CD, but have you factored in engine thrust for the airborne figures? My suggestion would be that a flying Lysander would lose somewhat less than 20mph given that the prop is pulling the aircraft against the recoil.
    Last edited by AdlerTag; 15th January 2010 at 23:54.

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    Quote Originally Posted by AdlerTag View Post
    ...have you factored in engine thrust for the airborne figures?
    Yes, these are covered by the expression ‘blah, blah, blah’ about halfway through my calculations!




    You are quite right of course; the speed of the aircraft is stable when the thrust equals the drag (related to the speed, squared) so as soon as the aircraft slowed the engine would begin to accelerate the aircraft until the thrust equaled the drag again!
    WA$.

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    Having checked back through my notes that are to hand and re-reading what I wrote rather than working from memory...

    The Lysander's cannon arrangement is pretty Heath Robinson, and obviously draggy. However my earlier point is that as far as I know there were no problems with how it worked, the reason it wasn't used is was it wasn't needed or, according to Bob Norris of 4 Sqn in France, they didn't have all the bits!

    There may be trial reports in the National Archives; I've not looked.

    As to some of the other issues, and as reminded by Ian, looking at R.Wallace Clarke's book - by May 1940 the British production Hispano cannon themselves should have been working OK; the problems with the cannon in Spitfires was due to having the guns laid on their side and this causing jamming of the drum feed - part of that being due to firing under g loads. The arrangement in the Lysander was upright (as designed) and unlikely to be firing under fighter-type levels of g. A question remains if the airflow may have affected the drum alignment, but would've helped with barrel and breech cooling.

    The off-centre nature of the recoil loading would be a minor issue perhaps in accuracy, but not as major as the emotional reaction might expect - remember aircraft like the Walrus had the engine's thrust line well out of alignment with the c of g, yet that worked in balance throughout the flight envelope. (And a Walrus was also fitted with a cannon for trials too... but we digress.)

    As to Creaking Door's impressive mathematics, firstly the guns wouldn't be fired in one burst of five seconds - more like half second bursts, presumably?

    I'm also intrigued as to where the energy dissipated and reused for cocking by the recoil mechanism in the cannon is factored in to the equation? Is that the third 'blah'?

    Anyone thinking the cannon Lysander was a bit of a poor idea as a beach-staffer needs to consider the rest of the bizarre variety pack developed on the design for the job. Both the Delanne Lysander and the Pregnant Perch were better engineering solutions in terms of the workmanship, but simply stupid (and late and complex) ideas given both were aft firing, giving the enemy the guaranteed benefit of shooting first.

    Delanne Lysander.




    The 'Pregnant Perch' which did fly - and crash. (Mock up):



    The Boulton Paul Turret Lysander (mock up).



    Photos either via RAF Museum or Westland Archives. As published in my Lysander book.

    Regards,
    Last edited by JDK; 16th January 2010 at 09:07.
    James K

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    Quote Originally Posted by Creaking Door View Post
    ...can’t resist a go at that! :diablo:

    Two Hispano-Suiza 20mm cannon firing 60 rounds each of AP-T, weighing 168g, at a muzzle velocity of 880m/s (in about 5 seconds)...

    ...one Westland Lysander with an empty weight of say 2000kg (assumed to be standing still in mid-air for ease of calculation).

    If the Lysander fired all 120 rounds the total momentum of the cannon ammunition would be:

    120 x 0.168 x 880 = 17,741 kgm/s

    If all that momentum is absorbed by the Lysander airframe (excluding blah, blah, blah):

    17,741 kgm/s = 2000 kg x V m/s

    V = 8.87 m/s

    V = 19.85 miles-per-hour

    So a stationary (empty) Lysander will be moving backwards at about 20mph by the time the cannon ammunition is exhausted...

    ...so a moving Lysander will lose about 20mph when the cannons fire (all their ammunition).

    A Lysander at maximum take-off weight (2877kg) will only lose about 14mph from its speed.

    (Awaiting somebody to spot a ‘school-boy-error’! )

    This is good stuff first my comments on flight Sims earlier was meant to Illustrate the point that firing cannons do slow aircraft down I would not suggest a flight sim is any where near accurate it just in my experience when trying to catch an EA where both aircraft are going flat out it firing the guns was not a good idea unless you were guaranteed a kill shot as you lost AS and fell further behind.
    Whether they are perfectly accurate in the amount of speed lost is irrelevant, the fact it was factored in as best they could, therefore you would have to accept that it happens.
    The calculations made above back this up and are more significant than I would have expected. The fact that these guns are very low down on the UC they would have a levering effect on the fuselage, enough I would think as I previously said to at least badly effect sighting of the Guns.
    when you have excluded the impossible whatever remains however improbable must be the truth
    Baz owns the second best Spitfire Replica in the World.

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