Typhoon Rockets

[Cthulhu]

I've had rockets bounce off gv's.  I wonder if that happened in real life.

Probably very common. The 60lb SAP round apparently could knock turrets off, but it depended on shot placement. The 25lb AP round might be able to penetrate the engine cover, but I'm guessing it lacks sufficient energy to penetrate anywhere else. The 60lb hollow charge is another matter entirely. The 60lb hollow charge was probably more effective. Impact velocity is largely irrelevant for a hollow charge, in fact the slower the better. IIRC the hollow charges of the day could penetrate 1.5x to 2.5x's the charge diameter (~2 x 3"), and nobody's had 6-inches of roof armor.

So you know the rockets chance to hit were 4% I believe (cant check my sources on this but i know was under 10%) In which
very few actually "killed" tanks, I know russian Il-2's had same problem where rockets were less then 10% hitting chance and only credible damage coming from tanks were tracking them, which was the idea at time to stop an enemy armored advance.

However most rockets were fired at softer targets, artillery, trucks for that nature bombs were used on tanks as well as the guns.

Absolutely. Post war assessments show that rocket attacks were far more effective at killing soft vehicles and breaking morale than they were at killing tanks.

[TonyJoey]

Probably very common. The 60lb SAP round apparently could knock turrets off, but it depended on shot placement. The 25lb AP round might be able to penetrate the engine cover, but I'm guessing it lacks sufficient energy to penetrate anywhere else. The 60lb hollow charge is another matter entirely. The 60lb hollow charge was probably more effective. Impact velocity is largely irrelevant for a hollow charge, in fact the slower the better. IIRC the hollow charges of the day could penetrate 1.5x to 2.5x's the charge diameter (~2 x 3"), and nobody's had 6-inches of roof armor.
Absolutely. Post war assessments show that rocket attacks were far more effective at killing soft vehicles and breaking morale than they were at killing tanks.

Yea I was reading that the SAP round could knock turrets off tanks. I think that in-game, with a direct hit to the turret, especially on the top, it should lose its turret, but if you chose the HE, you should be able to track a gv with a direct hit. Also it said it could peirce U-Boat hulls, so IMO I think that you should be able to sink a destroyer with 4 or so direct hits.

[Cthulhu]

Also it said it could peirce U-Boat hulls, so IMO I think that you should be able to sink a destroyer with 4 or so direct hits.

Not quite the same. IIRC a Swordfish punched a hole in the pressure hull so the sub couldn't submerge. The crew scuttled it later themselves. I doubt you'd do enough damage to cripple a DD.

[Kev367th]

 Missing the point -

Our Tiffy and Mossie rockets are pretty ineffective.

Already been stated they are not AP but HE ones.

In which case they must be 18lb HE rockets and not the 60lb Semi AP HE, or 60lb HE Shaped Charge. I can't find any ref to a 60lb strainght HE (as in the 18lb).

[Cthulhu]

Do you guys find the US rockets to be any more effective?

[Tony Williams]

Some extracts from Flying Guns – World War 2: Development of Aircraft Guns, Ammunition and Installations 1933-45:

It is worth commenting on these RPs. The origin of the British ones lay in the 3" (76 mm) UP (unrotated projectile) unguided AA rockets, which were designed to be fired in salvoes. They were fitted to warships early in the war but replaced as more AA guns became available. After noting the Soviet experience with rockets fired from aircraft, the British adapted the UPs for this purpose and two different warheads were eventually devised; a 25 lb (11.3 kg) solid AP head, intended for use against armoured targets, and a 60 lb (27 kg) HE head for use against ships. Typical striking velocities were 460 m/s and 350 m/s respectively. Battle experience soon reversed this preference, however. The AP proved to be very effective against ships and surfaced submarines, because on hitting the sea the trajectory would flatten out and it would skim just under the surface for some distance, hitting with enough force to penetrate hulls and boilers. On the other hand, it was found that a hit from the AP did not necessarily cause fatal damage to a tank (it had particular difficulty in penetrating Tiger tanks), whereas the HE would devastate anything it struck – armoured or not – and was therefore a good general-purpose ground attack weapon.
[RP60] British 3" rocket projectile with 60 lb HE warhead, at the RAF Museum, Hendon


The two RPs used by the USAAF had different histories. The 4.5" version originated from a 1940 request from the Ordnance Department to the National Defense Research Committee for help in developing a rocket primarily for use in aircraft. The availability of British research speeded the task so the first prototype was tested at the end of 1941. Somewhat bizarrely, the calibre of 4.5" (114 mm) was determined broadly by the specified warhead size and 330 m/s velocity, but specifically by the availability of surplus fire extinguisher tubes of that size! Unlike the British RPs, the 4.5" (designated the M8) had folding fins as they were launched from tubes. After significant problems with propellant quality, the M8 entered service in December 1943. In service, the tube-launching was found unnecessary and imposed drag penalties, so first the zero-length launcher from the USN's 5" (127 mm) HVAR (high velocity aircraft rocket) was utilised, then the HVAR itself was adopted, although the M8 remained in service alongside.  The M8 weighed 18 kg and the warhead carried 2.3 kg of HE and reached 260 m/s. The HVAR, which achieved 390 m/s, weighed 63 kg and carried 3.5 kg of HE.

and:

In contrast, one direct hit with a bomb or 60 lb RP meant certain destruction for the heaviest tank. However, their accuracy left a lot to be desired. Even under practice conditions, the hit rate for the RPs against tanks was no better than 5%. This was graphically illustrated by a demonstration put on by Typhoons against a captured Panther tank placed in the middle of an open field, helpfully painted white with large red crosses on it to make sure the pilots could see it. Of the 64 RPs fired (launched in a typical steep dive at ranges of 750-900 m), only three hit the tank. In battle, RP accuracy was considerably worse than this, with the official British calculation of hit probability against a single tank being 0.5% (in other words, 200 RPs had to be fired for each hit). Furthermore, some 20 – 30% of RP warheads failed to explode.
This fall in accuracy experienced in action may be attributed to the curious trajectory of the RP, which first dropped below the line of sight and then accelerated as the rocket motor took effect before it dropped again. Because of this it was generally desirable to fire them at a range of between 900-1,800 m. They were also very susceptible to side winds, with a mere 15 km/h wind being enough to miss the aiming mark by nearly 5 m, and the aircraft had to be absolutely steady at the instant of launching. This meant that a pilot needed a very cool and calculating head to ensure reasonable accuracy, something that was difficult to achieve in the heat of battle. It is worth noting that high-velocity cannon did not suffer from this problem, so would have experienced a much less significant fall-off in accuracy under combat conditions. RP accuracy was helped to some extent late in 1944 by the introduction of the modified Mk.IID gyro sight with calibrations suited to the RP. This presumably accounted in part for a measured improvement in the average RP miss distance between 1944 and 1945, from 57 m to just under 40 m.

Tony Williams: Military gun and ammunition website

[Yossarian]

Very interesting - thanks for posting!!

<S>

Yossarian

[SmokinLoon]

According to the HTC Trainer's Website under the "Relative projectile Strength" listing (I printed it out for quick ref.)...

The US and UK both use the same rockets.  The 3.5in, the 4.5in, and the 5in rockets.  So if the Typhoon's rockets are 'tarded in some way, the rest of the aircraft that uses the same rockets are 'tarded as well.

The 3.5in has a relative power of 140 (HE)
The 4.45in has a relative power of 93 (HE)
The 5in rocket has a relative power of 156 (HE)

Relative = 1/1000th of the 1k bomb vs a hanger.  In other words, it takes 7+ 3.5in rockets to = a 1000lb bomb damage wise. (1000 divided by 140 = 7.14). 

Both of the Soviet rockets are AP.  Resources say the Soviet rockets were highly inaccurate, but when they connected they were highly effective in *eliminating* German armor. 

I am not expert in using rockets, but I have tried and tried again and they seem to be of more use vs buildings than vs gv's.  This is the case for both the Soviet and US/UK rockets.

By the looks of things, it appears that these stats have been compiled by a third party (credit to SCJazz and Mudr).  It is too bad the HTC does not have an actual stat source of what gun/cannon and ordanance actually are and how their damages compare between HE and AP.  Is seems to be too much of a guessing game. 

Ah well... I guess we'll continue to pay and continue to shut up.     

[Kev367th]

I would guess then that the 3.5 inch Tiffy / Mossie rocket is the 18lb HE standard one.

The 60lbrs only came in -
HE Semi Armour Piercing
and
HE Shaped Charge.

Maybe it's just using a generic 18lbs one until the Tiffy / Mossie is remodelled, at which time they could give them the correct 60lbs rocket.

[Angus]

It has been stated that a salvo from a Mossie (8 rockets) would equal a cruisers broadside.
The weight of the warhead isn't everything there, since the attacker is already travelling at great speed that energy for penetration must be added. And if the salvo hits, it is all pretty well close...
It was belived (don't know if it was proved) that a rocket salvo like this hitting on the middle of a destroyer could actually break the ship.
Anyway, I do recall an account where a tank was inspected after receiving a direct rocket hit. It did penetrate and the blast killed the crew.
Small hole and crew in ugly bits, out of memory comes the front legbone or something of the sort.
I think this is from Closterman, not sure though.

[Jester]

It has been stated that a salvo from a Mossie (8 rockets) would equal a cruisers broadside.

It was belived (don't know if it was proved) that a rocket salvo like this hitting on the middle of a destroyer could actually break the ship.

Always heard this of the P-47 THUNDERBOLT with the 10x 5" HVAR Rockets and it was a DESTROYER's broadside.

5" (127mm) are the standard size for US Destroyer guns. I doubt there was a WW2 aircraft that could haul enough rockets to equal the firepower of a CRUISER - unless we start bringing up the 11" TINY TIM rockets - then I still think it would still be short.

 

[Tony Williams]

It depends on how you measure these things.

A 6 inch HE shell contained around 14 lb of explosive: the 60 lb RP also contained 14 lb. So a full load of eight RPs delivered as much HE to the target as a broadside from a cruiser with eight 6 inch guns.

However, the cruiser shells were travelling much faster and contained more steel, which meant that they not only penetrated more deeply but also created more fragments. OTOH, their shells were designed for use against ships and often were fitted with delayed-action fuzes so that they detonated inside the target; this was less effective in shore bombardment since they were buried in the ground by the time they exploded.

Tony Williams: Military gun and ammunition website

[Jester]

1.  True - some CL's had as many as 15x 6" guns.
2.  The Late model P-47's & P-38's could 10x 5" HVAR rockets.
3.  There are several other naval shells you are not mentioning - most Shore Bombardment was done with another kind that was not an "HE" shell in the regular sense but was a dedicated "Bombardment" shell that had a very thin skin so more explosive could be packed inside.

Anyway, this is like compairing dogs and cats - there really is no "Precise Way" to do it.

 

[Tony Williams]

I think that the original comparison was between the British 60 lb RPs and the most common type of British cruiser - which had eight 6" guns.

I know that the USN developed lightweight HE shells for shore bombardment for its battleship guns, but I wasn't aware that these extended across smaller calibres. Certainly the RN tended to use whatever was in the magazine, which would have been the standard HE shells. Whether they were able to set the fuzes to "instant" rather than "delay" for shore bombardment I don't know.

I agree, though - it's an apples and oranges comparison.

Tony Williams: Military gun and ammunition website

[Nisky]

I think ive got film of me bouncing a rocket off a T34 i was lmao i thought it was hilarious.