Aircraft Design and Specification - Documents

[oldpop2000]

With the introduction of aviation in RTW2, I thought it would be a good idea to start an aircraft design and specs thread. I don't know how applicable it will be to the game but it might help us all to understand how aircraft fly, are designed and perform. I am not an aeronautical engineer, maybe some of you are good mathematicians, that will be useful. Anyway here is my first document. It is free from NASA.


www.history.nasa.gov/SP-468/contents.htm

The next link is to the NASA Index of Aerodynamic Slides. It offers ways of change the aerodynamics of the aircraft and seeing how it performs along with a whole group of educational slides etc.


www.grc.nasa.gov/WWW/K-12/airplane/short.html

If you ask a question, I might have a document that I can provide to help explain your question. 

[oldpop2000]

Here is a WW2 Training Video on dive bombing - www.google.com/search?client=firefox-b-1-d&q=Dive+Bombing+techniques#kpvalbx=_UNdfXtKOM4Gt0PEPhbqvkAI44

[griffin01]

I think it is related to the topic - I would be very grateful if someone enlightened me regarding the possibility of successful torpedo delivery by jet aircraft and design considerations that would entail. My knowledge about aircraft is very limited, but I believe that most torpedo bombers were rather slow, and that launching torpedoes at high speeds tended to have explosive results, which is why I'm rather curious about it.

[oldpop2000]

Mar 4, 2020 12:31:08 GMT -6 griffin01 said:

I think it is related to the topic - I would be very grateful if someone enlightened me regarding the possibility of successful torpedo delivery by jet aircraft and design considerations that would entail. My knowledge about aircraft is very limited, but I believe that most torpedo bombers were rather slow, and that launching torpedoes at high speeds tended to have explosive results, which is why I'm rather curious about it.

Torpedoes have to be dropped from low altitude and at slow speeds. Having said that, there were jet powered torpedo bombers after WW2. The S-3 Viking was low and slow, ship attack aircraft that was primarily an ASW platform. There was a torpedo bomber version of the IL-28 Russian jet bomber, The P-8 Poseidon can carry and eject a torpedo with a parachute. Most people don't realize that the A-5 Vigilante, which ejected ordnance out the back, between the engines, could launch a torpedo with a parachute. 

You are correct that the WW2 torpedo bombers generally launched torpedoes at about 100 MPH or less at about 100 feet or less. It depended on the torpedo and the nation. 

So, with a jet, how do you launch a torpedo. Well, you can drop it with a parachute to reduce impact and as soon as the torpedo hits the water, the torpedo drive system ignites and away we go.

Remember that Anti-ship missiles were developed and used during WW2. The BAT was used by the US Navy, and the Germans had four, the Japanese had two. This was the technology of the future because you did not have to slow down, get close or drop these missiles from low altitude. Eventually they became guided missiles. They presented a much bigger challenge to  the target. By this time, the battleship had had its day and the targets available except for carriers were easier targets to damage. Another issue was the development of the  concept of mission killing instead of trying to sink a ship. It was far more cost effective to accomplish this, than sink the ship.

I hope this gives you a reasonably good answer. 

[brygun]

While I don't think I've got time to read in detail this I commend Ye oldpop2000 for adding this to the ye community haveth collection of lores.

[oldpop2000]

Mar 4, 2020 18:33:11 GMT -6 brygun said:

While I don't think I've got time to read in detail this I commend Ye oldpop2000 for adding this to the ye community haveth collection of lores.

Ay, lad, We are glad to have provided such lores and good words.

[oldpop2000]

I thought I would share this funny statement by the "The Flying Nun". When lift plus thrust equals load plus drag, anything will fly. Sally Fields was the Flying Nun. Actually, the statement is pretty accurate.

[rimbecano]

Mar 4, 2020 12:59:01 GMT -6 oldpop2000 said:

Torpedoes have to be dropped from low altitude and at slow speeds.

Combat experience in WWII proved this to be less true than was believed to be the case before the war. In fact, during the war it proved to be the case that dropping too low resulted in the torpedo entering at too flat an angle and slapping its belly on the water, resulting in damage. Optimal entry angles for the Mark 13 proved to be about 22-32 degrees, and as long as this was achieved, the torpedo could be dropped at a fairly broad range of speeds, especially once a wooden drag ring was developed, up to 410 knots in late '44. On one occasion in early '45, six torpedos were dropped from altitudes of 5000-7000 feet, of which five were observed to run hot, straight, and normal.

[oldpop2000]

From Navweaps:

These problems continued into the early war years, with a mid-1943 analysis of 105 torpedoes dropped at speeds in excess of 150 knots found that 36 percent ran cold (did not start), 20 percent sank, 20 percent had poor deflection performance, 18 percent gave unsatisfactory depth performance, 2 percent ran on the surface and only 31 percent gave a satisfactory run. The total exceeds 100 percent as many torpedoes had more than one defect. The early models were further handicapped by the need to drop them low and slow - typically 50 feet (15 m) and 110 knotswhich made the torpedo planes carrying them vulnerable to attack.

These problems were greatly reduced by the latter years of the war. Torpedoes had fin stabilizers, nose drag rings and tail shroud rings added, all of which worked to slow the torpedo after it was dropped so that it struck the water nose-first and at an acceptable speed. These improved the drop characteristics such that the recommended aircraft maximum launch parameters were increased to a height of 2,400 feet (730 m) and a speed of 410 knots.

A lanyard was attached to the tail of the torpedo. When dropped, the lanyard tripped a starting lever, but a water trip delay valve prevented the combustion flask from lighting off until the torpedo had entered the water. When dropped at 150 knots or more, the torpedo would enter the water at an angle of between 26 and 30 degrees. The water needed to be at least 150 feet deep (45 m) and the torpedo assumed its preset running depth after water travel of 300 yards (275 m). The exploder mechanism was armed after water travel of 200 yards (180 m). Depth could be set up to 50 feet (15 m).

The addition of the nose drag ring improved aerodynamic performance by stabilizing the torpedo in flight and reduced air speed by about 40 percent. It also acted as a shock absorber when the torpedo struck the water. The tail shroud ring improved the water run by reducing hooks and broaches and by eliminating much of the water roll which had characterized the earlier Mark 13s. Hot, straight and normal runs now approached 100 percent. To speed availability of the much improved torpedo, the Bureau of Ordnance had tail assemblies built with the shroud ring attached and then shipped these to the fleet for upgrading the existing inventory. By the fall of 1944, the modified torpedo was in general use by the front-line carrier units which were enthusiastic in their praise. On one occasion in early 1945, six torpedoes were dropped from altitudes between 5,000 and 7,000 feet (1,500 to 2,100 m). Five out of the six were observed to make their runs hot, straight and normal. By the end of the war, the USN considered the Mark 13 to be the best aircraft torpedo produced by any nation and it remained in service until 1951.

Notice: Low and slow. In the early sea battles like Coral Sea, Midway, Eastern Solomon's and Santa Cruz, this was the pattern of drop for all torpedo bombers. It wasn't until 1944 that they solved the problem  but torpedo attacks by aircraft were few except for the sinking of the Yamato. BTW, my father flew in torpedo bombers and dive bombers and that is how he described the attack mode.


web.archive.org/web/20051210061123/http://www.geocities.com/Pentagon/1592/ustorp2.htm

[oldpop2000]

Here is another informative but actually interesting site. It Zeno's warbirds video's on Youtube.

www.youtube.com/user/ZenosWarbirds?reload=9


www.youtube.com/watch?v=CPUc-cWAzBg - This is a torpedo bombing training video from WW2

[griffin01]

Mar 4, 2020 12:59:01 GMT -6 oldpop2000 said:

Mar 4, 2020 12:31:08 GMT -6 griffin01 said:

I think it is related to the topic - I would be very grateful if someone enlightened me regarding the possibility of successful torpedo delivery by jet aircraft and design considerations that would entail. My knowledge about aircraft is very limited, but I believe that most torpedo bombers were rather slow, and that launching torpedoes at high speeds tended to have explosive results, which is why I'm rather curious about it.

Torpedoes have to be dropped from low altitude and at slow speeds. Having said that, there were jet powered torpedo bombers after WW2. The S-3 Viking was low and slow, ship attack aircraft that was primarily an ASW platform. There was a torpedo bomber version of the IL-28 Russian jet bomber, The P-8 Poseidon can carry and eject a torpedo with a parachute. Most people don't realize that the A-5 Vigilante, which ejected ordnance out the back, between the engines, could launch a torpedo with a parachute. 

You are correct that the WW2 torpedo bombers generally launched torpedoes at about 100 MPH or less at about 100 feet or less. It depended on the torpedo and the nation. 

So, with a jet, how do you launch a torpedo. Well, you can drop it with a parachute to reduce impact and as soon as the torpedo hits the water, the torpedo drive system ignites and away we go.

Remember that Anti-ship missiles were developed and used during WW2. The BAT was used by the US Navy, and the Germans had four, the Japanese had two. This was the technology of the future because you did not have to slow down, get close or drop these missiles from low altitude. Eventually they became guided missiles. They presented a much bigger challenge to  the target. By this time, the battleship had had its day and the targets available except for carriers were easier targets to damage. Another issue was the development of the  concept of mission killing instead of trying to sink a ship. It was far more cost effective to accomplish this, than sink the ship.

I hope this gives you a reasonably good answer. 

It does, indeed, thank you. Did the parachute detach somehow after hitting the water? I presume that it would affect its performance, even if it wasn't a significant effect.

[oldpop2000]

The Mark 44 had a parachute retarding system to slow entry into the water. It detached after the torpedo hit the water. www.navweaps.com/Weapons/WTUS_PostWWII.php

[dorn]

If torpedo bombers are focus, I would more focus on British as Royal Navy focus on torpedoes and night attacks as they know that they are backward in quality and quantity of aircrafts. However I do not know good sources.

[oldpop2000]

Mar 5, 2020 13:57:42 GMT -6 dorn said:

If torpedo bombers are focus, I would more focus on British as Royal Navy focus on torpedoes and night attacks as they know that they are backward in quality and quantity of aircrafts. However I do not know good sources.

www.navweaps.com/Weapons/WTBR_Main.php

[oldpop2000]

You might find this useful about torpedo bomber attacks