homepage Forums Air Combat & Civil Aviation Rise of Flight - The First Great Air War WWI sim, based on the IL-2 engine announced

Dave, I somehow figured that you would have something in your extensive image collection.

Is that from Harry Woodman's book on air armaments?

As far as the bombs wouldn't the slipstream of the propeller cause the bombs to avoid traveling forward and instead start to favour heading downwards?

I can't imagine the WW1 planes dive bombing though, unless there was a similar mechanism like the Stuka which triggered to circumvent this problem. As mentioned, the WW1 Cooper mechanism will only engage at a flatter angle.

S!

That's what I'm thinking

Whereas the stuka rack had to be. I've been practising with the Sturmovik and getting better at low angle pickle tossing, it's more of a feel than a calculation for me.

Aircraft armaments expert and author Dr. Emmanuel Gustin wrote this brief history on the development of dive-bombing:

The Origins of Dive Bombing

The concept of dive bombing was certainly not unique to the German Luftwaffe. The theoretical basis for it is simple enough, that it would come to different minds in different places and at different times. It would probably be unjustified to look for the "inventor" of dive bombing.

In normal (horizontal) bombing the released bomb has a horizontal, forward speed vector given to it by the movement of the aircraft. To this a vertical acceleration is added, caused by the pull of gravity, which causes the bomb to fall. The combination of the two results in a parabolic curve, which is distorted by the drag of the bomb and the wind. The basic idea of dive bombing is to make the speed vector of the aircraft coincide with the direction of gravity -- vertical -- so that the trajectory of the bomb becomes a straight line instead of a complicated curve. This greatly reduces the problems of bomb aiming. Because the bomb is usually released from lower altitude and at higher speeds, the effects of the wind are also minimised.

The technique was first used during Word War I. The first officially acknowledged dive bombing attack seems to have been made by Lieutenant Harry Brown of the RFC (Royal Flying Corps) who sank a munitions barge in 1917. After the end of the war the RAF (Royal Air Force) conducted research and experiments, but finally decided that the method was too dangerous and halted its development. Instead, the British chose to concentrate their efforts on the creation of a strategic bombardment force. The FAA (Fleet Air Arm) kept the idea alive, but the development on its aircraft was seriously hampered by the RAF control over all aircraft, including shipboard aircraft.

The development of dive bombing continued in the USA. The USMC (US Marine Corps) practised dive bombing, although seldom at angles of more than 45 degrees, during operations in Haiti in 1919. A more refined form of the technique, influenced strongly by aviators who had flown in Europe during W.W.I, was used by them during the US intervention in Nicaragua in 1927. During these years, the USMC pilots also included spectacular dive bombing demonstrations in their air show routines. The USN (US Navy) adopted dive bombing as doctrine, not to provide ground units with tactical air support (as had been the goal of the USMC) but as an effective method to hit enemy ships -- relatively small, moving targets. The aircraft used during these years were developments of the Curtiss Hawk family of fighter biplanes, the F6C and BF2C. The name of `Helldiver' was attached to these aircraft, although this would not become officially the name of an American aircraft until the Curtiss SB2C was introduced, during W.W.II.

As noted above, the early dive-bombing techniques (and experiments) of the WWI-era involved angles much lower than those used in WW2. For that matter, even sustained diving during combat in fighter aircraft rarely exceeded 45-60 degrees from the horizontal. Here's part of the text from a Royal Aircraft Factory study written in 1917 titled Terminal Velocity of S.E.5.:

SUMMARY.--The terminal velocity of S.E. 5 at 10,000 ft. is 265 m.p.h. indicated with the engine on, and 255 with it off. In the former case the aeroplane acquires a velocity of 250 m.p.h, in the first 1,500 ft. of drop. These figures apply to the geared 200 h.p. Hispano engine. The effect of the engine is so doubtful that the speeds with the 150 h.p. engine have not been worked out, but they would probably be rather higher on account of the smaller breaking effect of the smaller engine and airscrew.

The conditions of air fighting at the present time make it necessary for pilots to dive their machines very steeply. It is stated that aeroplanes are dived "vertically" for several thousand feet. It is probable that the actual angle of the path to the horizon is nearer 45-60 degrees (the tendency of an observer in an aeroplane is always to overestimate the steepness of a dive).

The following calculations, which refer to S.E.5, give support to this suggestion, for they show that a speed of the order of 200 m.p.h, would soon be attained on an aeroplane capable of anything like 120 m.p.h, flying level, whereas it appears that so high a speed as this is seldom reached in practice. Some notes on the stresses which occur in diving at these speeds are given in another report.

For those of you interested in learning more about WWI aviation history, and like Dantes, specifcally about some of the British bomb carriers used in WWI, here's a link to a host of great articles online that were previoulsy published in THE '14 -'18 JOURNAL (in PDF file format):

http://asww1ah.0catch.com/article.htm

Maybe we will be needing more powerful computers to fly Knights:



This week's update shows the le beffroi of Lille, and the in-game RT shadow casting being enabled with the Newtonika game engine:

http://www.gennadich.com/index.htm#

Taking it back OT again, but the Stuka comments got to me going...

I've seen the explanation in a number of places that says the pivoting bomb cradle on a Stuka was there "so that the flight of the bomb would now be outside the arc of the propeller". The Stuka would be in a high-drag configuration with its dive brakes extended, but I doubt it's going slow enough the bomb would out-accelerate the aircraft downward during an 80-90 degree dive angle release. It's said that the Stuka's airspeed would stabilize around 350 mph.

I could be wrong - I don't know the specs on that bomb - drag coefficient, its terminal velocity, etc., but it's not like the Stuka is just hanging there on a string, motionless in mid-air, dropping a bomb forward through its propellor. I doubt that clearing the prop was the true reason for the extending bomb cradle.

One of the sites with the "explanation" of the Stuka bomb cradle:
http://home.freeuk.net/johndillon/ju87.htm#Profile%20of%20a%20Stuka%20dive.

A delivery with an 80-90 degree dive angle could help in accuracy and aiming - less arc, etc. - but it could also leave the bomb fairly close to the aircraft longer than in a more shallow delivery - the bomb wouldn't fall away from the aircraft as much on release. I'd suspect the cradle was there to eliminate possible contact with the underside of the aircraft and especially with the fixed landing gear.

Wasn't there an automatic pullout initiated at or before the bomb release? This would lessen any tendency for bomb/aircraft collisions... or for any possible "bomb dropping through the prop arc" activity.

I've got a good number of real bomb-dropping hours, but I haven't found any hard data to support or debunk the idea. If anybody has some real (German or other) data on the reason for the Stuka bomb cradle, I'd like to see it.

Also, as bombs release, it sometimes takes a second or two for them to stabilize, for the fins to take effect.
Take a look at the inert 500 pounders flopping around in this photo - typical:
http://www.fotosearch.com/UNY515/126-06251/

________________________________________
Back on topic... a couple links.

Article on WWI bombing:
http://www.centennialofflight.gov/essay/Air_Power/WWI_Bombing/AP3.htm

WWI info site:
http://www.firstworldwar.com/airwar/index.htm

Papa_K

And the real Beffroi:



Pretty good match!

I really hope this is coded as tightly as Il-2. It's a point in their favour that they're Russian developers- there seems to be more sympathy for the guy with a crapp computer.

This week's GT update is a video, showing RT self-shadowing effects!

To download and check out the video go here:

http://www.gennadich.com/files/589/file/multi/GT_Promo5.zip

Even the bracing wires of the featured Nieuport 17 get into the scene.

Beautiful! Not like the coarse self-shadowing in Lock-On.

Wow !!!

*silently in awe*

This self shadowing to me is a big step ahead.

I only fear the final system requirements now...

Our rigs at the office are 3ghz Prescott/GF6600GT which is really modest to todays standards and i don't think the final _flyable_ sys reqs will be much higher than that. Min specs should be even lower. So fear not

Tim Ivanov
KotS DevTeam

Good to see you at SimHQ Tim!

(Better late than never, well, you only have 6 posts so far...)

Thanks for info Tim :), all the best to the team.

Didn't they make a Camel with a 37mm?

I know that 37mm automatic cannons were used by scouts on the Russian front.

I was under the impression that accurate dive bombing was still fairly new in the '30s (even if it had be done as early as '17).

Best news about KotS I've seen...and thats saying alot!

Nice. Very natural looking detailed shadows, great lighting.

I've wondered about this before... do development teams test the highest settings at 3 fps, or is there always one uberPC in the office?

thatsa sweet lookin Nieuport nice show

Whom ever made this a "Sticky" - please present your feet so that they may be properly kissed. It has been getting harder and harder to find this thread mixed in with all the other, somewhat relevant, IL2 threads.