Question on Mosquito Paint Scheme

[11bravo]

3 hours ago, Blimpyboy said:

A genuine head-scratcher, given the typical ‘accuracy’ and ‘precision’ of these rockets in their singular configuration!

LOL!   Given that there is little chance that both motors would burn out at the same time, I’m not certain that a “duplex” RP would even hit the water let alone the target!!

Edited July 25, 2020 by 11bravo

[Dave Swindell]

6 hours ago, 11bravo said:

LOL!   Given that there is little chance that both motors would burn out at the same time, I’m not certain that a “duplex” RP would even hit the water let alone the target!!

If you read the text on the last page posted by Chris above, the rockets weren't fired as a duplex unit on the operational fit, the arrangement shown earlier with the duplex rockets was a trials installation.

The original setup with 8 launchers allowed firing in pairs (4 pairs, fired separately, one rocket from each wing, inboard to outboard), or as a salvo (4 pairs, fired automatically in rapid succession, one rocket from each wing, inboard to outboard).

The double stacked rocket rails were fitted with a splitter plug for two pigtails to fit into one socket. The two lower rockets were plugged to the inboard rail, and the two upper rockets were plugged into the outer rail.

The firing selector mechanism remained the same, so if pairs was selected the two inboard rails would be triggered on the first shot, firing all 4 lower rockets, and the two outboard rails would be triggered on the second shot, firing all 4 upper rockets. With a salvo shot, again all 4 lowers would be fired together first, then a fraction of a second later, all 4 upper rockets would be fired.

The rockets were never precision ballistics, but you didn't need pinpoint accuracy with the relatively large target a ship provided, you only needed one big hole below the waterline to do serious damage.

[Blimpyboy]

2 hours ago, Dave Swindell said:

firing all 4 lower rockets,

Yeah, hence the head-scratching. One can only imagine the ‘accuracy’ of those!

Edited July 25, 2020 by Blimpyboy

[SafetyDad]

Aviaeology in their instructions to 'Special Edition - Canadians in Coastal Command #3'  provide detailed information about the colours carried by these Mosquitos, and while I'm sure that many posters here are aware of what I am about to say,  I thought I would include it for the sake of completeness.

 

Aviaeology describe the Mosquitos being initially painted in the standard night-fighter scheme of Medium Sea Grey overall with Dark Green disruptive pattern on the uppersurfaces. Then they were overpainted Extra Dark Sea Grey over Sky undersurfaces. So far, so good.

 

But an 'ad hoc' (their term) colour scheme variation is then described, where 'a noticeably lighter grey - closer to Dark Sea Grey- (was) sprayed directly over the Night Fighter Scheme on the upper and side surfaces'. (Direct quote). 'Sky may have been used on the undersurfaces, but it also seems probable that the Medium Sea Grey was retained untouched'. (again quoting). 

A key point in their description of these schemes is that the uppersurface paint application could be thin, very thin, to the point where the original underlying MSG/DG pattern could be made out. That may well explain some of the points highlighted in the comments around the first colour picture. The decal instructions provide photographs of RF882 EO@Z where this 'translucent' paintwork has been applied, and the shadows of the original MSG/DG paint can be made out.

 

Not my primary area of expertise, so I apologise in advance if I am stating the obvious.

 

SD

 

 

[Dave Swindell]

3 minutes ago, Blimpyboy said:

Yeah, hence the head-scratching. One can only imagine the ‘accuracy’ of those!

No different from the accuracy of the previous 8 rocket setup. The launch rails were found to have little effect on accuracy compared to zero length launching which became the norm post war.

This was a large gauge shotgun being fired at close quarters at a big target, not pinpoint precision at extreme range, and it was very effective against shipping and Uboats.

[Blimpyboy]

2 hours ago, Dave Swindell said:

but you didn't need pinpoint accuracy with the relatively large target a ship provided, you only needed one big hole below the waterline to do serious damage.

Well, you sorta did need accuracy; getting a hole below the waterline isn’t easy - especially against a moving ship!

A ship is a much different target to a sub, and harder to render non-seaworthy through ricochets, let alone direct hits. 

 

Actually hitting (or even near-missing) targets was always the chronic failure of the RPs. Thankfully, the Mossies’ cannons did a much better job in damaging ships.

 

 

[Graham Boak]

It was found that the rockets didn't ricochet, but continued to travel underwater, hitting the ship under the waterline, and this became the preferred means of attack.  The rockets were highly successful in crippling the surviving German merchant fleet (and hence iron ore supplies) much more so than the torpedo attacks had been.  Gunfire would indeed do damage to ships superstructure, so very useful in suppressing flak, but ineffective at actually sinking anything above a trawler.

 

Subs are smaller targets than large merchant ships but equally vulnerable to rocket hits.

 

The accuracy of a single rocket against a point target such as a tank or gun is indeed small, but the value of a salvo, or indeed several salvos, at a large target is quite another matter.

[Blimpyboy]

31 minutes ago, Dave Swindell said:

No different from the accuracy of the previous 8 rocket setup. The launch rails were found to have little effect on accuracy compared to zero length launching which became the norm post war.

This was a large gauge shotgun being fired at close quarters at a big target, not pinpoint precision at extreme range, and it was very effective against shipping and Uboats.

 

I believe the trial two-rocket installation posted earlier was intended to be fired as a single unit - twice the bang for your buck, as it were.

The later, operational iterations did indeed fire separately (these were fitted with all four fins as per the Aviaeology diagrams), with the lower rocket shearing the connection with the upper when fired.

 

The ‘buckshot’ effect was also largely ineffective and the vast majority of firings achieved not one impact - against ships or land-based targets.

The true effectiveness of RPs against U-boats and surface craft was predicated largely on piercing the pressure hull, not detonating against it. Some rockets achieved below-waterline damage of surface vessels through impacting short of the target (intentionally and - mostly - accidentally) and continuing to travel through the water; however, actual sinkings through this mechanism were minimal.

 

Ultimately, only an extremely small number of U-boats were actually sunk/rendered non-operational by RPs - cannon and bombs arguably were the greatest cause of damage and loss.

 

RPs seem to have been one of the most overrated weapons, in terms of accuracy and lethality. Luckily, their effect on morale and ‘shaping’ of enemy manoeuvre far outweighed the above-mentioned technical deficiencies!

 

Edited July 25, 2020 by Blimpyboy

[Blimpyboy]

2 minutes ago, Blimpyboy said:

🤔

 

Edited July 25, 2020 by Blimpyboy
Double post. Stupid ‘phone.

[Dave Swindell]

8 minutes ago, Blimpyboy said:

Well, you sorta did need accuracy; getting a hole below the waterline isn’t easy - especially against a moving ship!

A ship is a much different target to a sub, and harder to render non-seaworthy through ricochets, let alone direct hits. 

 

Actually hitting (or even near-missing) targets was always the chronic failure of the RPs. Thankfully, the Mossies’ cannons did a much better job in damaging ships.

 

The rockets were sufficiently accurate to be a very effective weapon. The cannon & machineguns damaged ships and killed or wounded personnel. The rockets disabled and sank them.

 

4 minutes ago, Blimpyboy said:

I believe the trial two-rocket installation posted earlier was intended to be fired as a single unit - twice the bang for your buck, as it were.The later, operational iterations did indeed fire separately (these were fitted with all four fins as per the Aviaeology diagrams), with the lower rocket shearing the connection with the upper when fired.

 

The ‘buckshot’ effect was also largely ineffective and the vast majority of firings achieved not one impact - against ships or land-based targets.

The true effectiveness of RPs against U-boats and some surface craft was predicated largely on piercing the pressure hull, not detonating against it. Some rockets achieved below-waterline damage of surface vessels through impacting short of the target (intentionally and - mostly - accidentally) and continuing to travel through the water; however, actual siblings through this mechanism were minimal.

 

Ultimately, only an extremely small number of U-boats were actually sunk/rendered non-operational by RPs - cannon and bombs arguably were the greatest cause of damage and loss.

 

RPs seem to have been one of the most overrates weapons, in terms of accuracy and lethality. Luckily, their effect on morale far outweighed the above-mentioned deficiencies!

From mid 1943 it was the primary airborne weapon in use against shipping and surfaced U boats, and the RP-3 continued in service with the RAF and FAA into the 60's, if it was as ineffective as you seem to be suggesting I very much doubt this would have been the case.

[Blimpyboy]

54 minutes ago, Graham Boak said:

 

The accuracy of a single rocket against a point target such as a tank or gun is indeed small, but the value of a salvo, or indeed several salvos, at a large target is quite another matter.

Only to a degree - a ship is big, but only depending on the aspect you attack it from. Plus, a salvo that misses (as most RP salvos did) still, well, misses.

Viewed from abeam ships look big, but you have a higher probability of your stick missing when attacking, as your aiming point is exactly that - a point.

Viewed from a fore-and-aft perspective, a ship looks much smaller; however you have a much greater probability of your stick hitting it along its length (you have an aiming/impact line rather than a point).

 

Consider a biggish bridge: a large target, arguably the length of a smallish coaster; however, very difficult to hit with multiple rockets or bombs, especially when fired at from abeam.

And it’s not moving.

 

A diagonal run along the fore-and-aft would result in a much greater probability of hit, and maximise the damage caused by any hit (think the first Black Buck run), yet many strike images from WW2 show runs from abeam!

 

Ultimately, they fought with what they had, and we certainly can’t argue the contribution RPs made, even if it was largely psychological - it still posed a threat that had to be honoured.

Edited July 25, 2020 by Blimpyboy

[Blimpyboy]

27 minutes ago, Dave Swindell said:

if it was as ineffective as you seem to be suggesting I very much doubt this would have been the case.

Ineffective is perhaps the wrong word. I would say instead that they did not achieve a level of accuracy and lethality that would make them more lethal or effective than free-fall bombs.

They certainly had/have a psychological effect far beyond their actual lethality and material effects (consider the Typhoon/anti-armour issue); however, that is largely a matter of hindsight and better intelligence.

 

The chief reason for their ongoing use, I contend, is that they were pretty much all that was in the inventory (as were good ol’ dumb bombs - therefore, beggars can’t be choosers.

What other same-cost/simple to use alternative was there?

 

Rockets are nice and lightweight, cheap, and increase your stand-off when compared with free-fall bombs, so you live with the trade off that survivability gives you over accuracy and expenditure.

 

In the same vein, heavy bombing was equally as ineffective in many instances, but there was just no alternative weapon system. So, many countries still dumped tons of unguided iron bombs well into the 90s, despite the existence of PGMs.

Edited July 25, 2020 by Blimpyboy

[Graham Boak]

I suggest a study of the operations against the German convoys would enlighten you as to the success of the rocket as compared with its alternatives.  Individual attacks by bomb, torpedo or even naval gunfire offered equal at best or worse chance of success - considerably less so in the case of bombing.   If not every rocket attack sank a submarine, neither did every bombing attack or depth charge  or cannon.  Hence the reason of mass attacks rather than the "lone ranger" type.  The reason the RAF, the USN and other forces switched to rocket attack was due to its greater success and the reduced  losses involved.  It is not as though they had had little experience with the other methods.  Or, indeed, any shortage of other weapons to use.  It was not a case of being all you have in the inventory, but a new weapon being introduced (after considerable experimentation with less successful ideas for new weapons in the role) because of its greater value, and steadily replacing the available but more expensive and less effective alternatives.   So as a weapon system it was cheaper, easier to use,  from a wide range of aircraft types, with greater effectiveness and lower losses.  What's not to like?

 

Attacking along the length of the ship was the recommended method for dive-bombers, and this is why AA protection was clustered at the rear.  For level bombers a greater chance of success was along a diagonal, but for low-level attacks beam attacks were more profitable and less risky.  They also required less training, a not inconsiderable gain.

 

The comment about HE heads was demonstrated in practice by the abandoning of the 60lb head for shipping work in favour of the 25lb SAP head, and vice versa for ground attack work, though it was often found that more damage could be done inside a ship by the continued burning of the rocket after impact, when this occurred.

[stever219]

41 minutes ago, Blimpyboy said:

 

I believe the trial two-rocket installation posted earlier was intended to be fired as a single unit - twice the bang for your buck, as it were.

The later, operational iterations did indeed fire separately (these were fitted with all four fins as per the Aviaeology diagrams), with the lower rocket shearing the connection with the upper when fired.

 

The ‘buckshot’ effect was also largely ineffective and the vast majority of firings achieved not one impact - against ships or land-based targets.

The true effectiveness of RPs against U-boats and surface craft was predicated largely on piercing the pressure hull, not detonating against it. Some rockets achieved below-waterline damage of surface vessels through impacting short of the target (intentionally and - mostly - accidentally) and continuing to travel through the water; however, actual sinkings through this mechanism were minimal.

 

Ultimately, only an extremely small number of U-boats were actually sunk/rendered non-operational by RPs - cannon and bombs arguably were the greatest cause of damage and loss.

 

RPs seem to have been one of the most overrated weapons, in terms of accuracy and lethality. Luckily, their effect on morale and ‘shaping’ of enemy manoeuvre far outweighed the above-mentioned technical deficiencies!

 

I think you’ve been over-thinking this.

 

A beam-on attack gives you a bigger target, for example a 400-odd foot long ship has a beam of around fifty to eighty feet, so harder to hit from head on.  A head on attack also creases the chances of a wasted shot as some of the RPs might glance off the hull plating due to the curve at the bows producing a shallower impact angle.  The chances of knocking out the bridge on most merchant ships of the time, with the possible exception of tankers and transports, is also compromised by the amount of high-rise gear (masts, derricks, etc) ahead of the superstructure.

 

A beam attack allows an opportunity to breach more than one watertight compartment, be it hold, boiler room, engine room or bunkers which, although maybe not resulting in an outright sinking, will increase the probability of crippling the ship and creating a liability to the operator (do we stop to pick up the crew, can we put a damage control party aboard, can we get a tow line into her, do we have to finish the job to deny the enemy an attempt at salvage?).

 

Underwater impacts by RPs could be devastating; remember the Dambusters?  The water behind the exploding RP acts as a tamper, directing the blast forwards much like a modern shaped charge, cutting a hole in the hull and then allowing the pressure of the water to amplify the damage.  There are many instances of ships being lost because, having been holed below the waterline, bulkheads have collapsed because the ship’s remained under way long enough to overload the bulkheads.

[Work In Progress]

 

39 minutes ago, Blimpyboy said:

you live with the trade off that survivability gives you over accuracy and expenditure.

You seem to be labouring under a misapprehension about WW2 era unguided bombs, and indeed WW2 era munitions generally.

Almost all of them missed, especially against moving targets.

 

I would hazard a bet that in terms of number of units expended, versus actual targets (defined as anything smaller and more specific than "a city-region") actually struck with military effect, the 3in RP clocked as good or better hit rate than any WW2 pistol , rifle, machine gun or aircraft cannon cartridge, any form of mainstream artillery, or any free-fall bomb with the exceptions of Tallboy, Grand Slam, Upkeep and the two nukes.

Edited July 25, 2020 by Work In Progress

[Blimpyboy]

Oh, I’m not saying they weren’t successful, not at all. Indeed, the mass with which they were employed is a testament to that. I’m simply pointing out the horrendous lack of accuracy and precision inherent to RPs!

RPs are just an excellent case study of a weapon that is technically and somewhat nostalgically overrated weapon, particularly when one compares wartime claims with post-war studies. Hindsight, hey?

 

Historically, too, free-fall bombs were responsible for the greater number of axis naval and merchant shipping losses to allied air attack - however; this comparison does not take into account the relatively limited period of time that rockets were used contemporaneously with bombs.

[Work In Progress]

5 minutes ago, Blimpyboy said:

RPs are just an excellent case study of a weapon that is technically and somewhat nostalgically overrated weapon,

Over-rated compared to what?

There is literally nothing "inherently accurate" about a 500 lb free-fall bomb.

Unlike a bomb a .303 rifle cartridge has a degree of inherent accuracy which can actually be measured in combination with a given rifle or machine gun barrel, but they still only go where you point them. Overall it took 45,000 rounds of small-arms fire to kill a single soldier.

Edited July 25, 2020 by Work In Progress

[Blimpyboy]

2 minutes ago, Work In Progress said:

 

I would hazard a bet that in terms of numebr of units expended, versus targets actually struck, the 3in RP clocked as good or better hit rate than any WW2 pistol , rifle, machine gun or aircraft cannon cartridge, any form of mainstream artillery,

Ooh, big call!

 Number for number, over the period of their use, I would argue that, for sure! I just not sure I have the time left to do the research! ☹️

[Blimpyboy]

3 minutes ago, Work In Progress said:

Over-rated compared to what?

Overrated in their technical effects - accuracy and precision.

As has been claimed by many studies, their psychological effects far outweighed the damage and destruction they caused on the battlefield (albeit, this stems principally from use against land-based targets).

Edited July 25, 2020 by Blimpyboy

[Work In Progress]

2 minutes ago, Blimpyboy said:

their psychological effects far outweighed the damage and destruction they caused on the battlefield

Ok then, other than Tallboy, Grand Slam, Upkeep and the two nukes, name me a single piece of projectile or explosive ordance used in WW2 for which that was not true.

Edited July 25, 2020 by Work In Progress

[Blimpyboy]

8 minutes ago, Work In Progress said:

WW2 era unguided bombs, and indeed WW2 era munitions generally.

Almost all of them missed, especially against moving targets.

I would absolutely agree; however a near miss from a 250 lb HE bomb will cause much more target damage - if not destruction in many instances - than a near miss at the same distance, from a 60 lb rocket warhead,

[Work In Progress]

1 minute ago, Blimpyboy said:

I would absolutely agree; however a near miss from a 250 lb HE bomb will cause much more target damage - if not destruction in many instances - than a near miss at the same distance, from a 60 lb rocket warhead,

A near miss from a 250lb HE causes ZERO damage to a large ship

[Blimpyboy]

1 hour ago, Work In Progress said:

A near miss from a 250lb HE causes ZERO damage to a large ship

Um, the underwater shock and bubble effects of 250 lb of HE can have some pretty nasty effects on parts of a large vessel - depending on the miss distance, an underwater explosion can cause more damage than a direct hit. Especially in comparison to 60 lb at the same miss-distance.

 

https://apps.dtic.mil/dtic/tr/fulltext/u2/a326738.pdf

 

https://www.amw.gdynia.pl/images/AMW/Menu-zakladki/Nauka/Zeszyty_naukowe/Numery_archiwalne/2015/ZN AMW_2015_2/Szturomski.pdf

 

 

Edited July 25, 2020 by Blimpyboy

[Blimpyboy]

There seems to be a smidge o’ fuss about the ol’ RP.

 

This is not BB singling out and saying the RP was not a valid or effective weapon, and it’s certainly not a case of saying it’s the worst weapon in the history of WW2 (PIAT, anyone?); nor is it the casting of aspersions on the efforts of those who designed the things and - most importantly - those who carried and fired them in anger.

 

It’s just an observation on the dire ballistic spread of RPs in general - a trait shared with any number of, if not all, aerial-delivered weapons.

BB’s vintage has given him much experience in the firing and dropping of unguided stuff dating from the cooling of the earth’s crust, and he knows only too well how effectively even the worst weapons can work when they actually hit what one is aiming at (he does love the Zuni...).

 

For those with an eye for academic history, it should be noted that warfare is dotted with interesting technical tidbits like the RP debate. That’s the beauty of analysing with hindsight - hopefully, we can learn from, and improve on things!

 

Still, BB unreservedly apologises for ruffling any feathers.

Can we still be friends?

Edited July 25, 2020 by Blimpyboy

[Blimpyboy]

1 hour ago, stever219 said:

I think you’ve been over-thinking this.

Not really, it’s a tactical principal. And training.

 

Assuming a direct hit..,

If you have a fore-and-aft hit, you run through more compartments along the length of the vessel. Plus, you only face the defences from a very small cross section of the ship.

If you have a beam-on hit, your weapon only runs the width of the ship (less straight-line real estate and therefore less compartments/‘stuff’, and you face all the defences along one whole side of the vessel.

 

Also (assuming a direct hit along your axis of approach), a salvo along the ship’s longitudinal axis has a greater probability of multiple hits. Even multiple near misses that cause damage will hopefully be achieved along the target’s length.

 

A salvo against the beam generally results in less munitions hitting the ship, or even missing close enough to do damage. Unless, of course, you adopt a straight-in approach, which is generally frowned upon, to avoid flying into your target!

 

Of course, always hitting what you aim at and steer against is the bigger question...

Edited July 25, 2020 by Blimpyboy