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Freiwillige
06-28-2009, 03:32 PM
Does anybody know if Canopy drag is modeled in the Sim? Like if you fly with it open does the induced drag slow your bird?

TinyTim
06-28-2009, 03:40 PM
AFAIK, it does. Haven't tested it tho.

Wildnoob
06-28-2009, 04:00 PM
I have a idiot doubt.

mainly the Japanese pilot's I belive, wat was the deal with fly with the canopy open most of the time?

heat of the pacific in the summer?

I know that the P-38 pilot's suffered a lot with heat during the summer due to the canopy could not be opened because the wind turbulance on the tail that would be caused by the change of the air flux, altough the plane had a heating system, it doen't have a refrigeration one, at least early in the war as far as I know, so normally they flew just with summer clothing such as shorts.

don't have sure of that, sorry for the OFF question, but in a summary this would be one of the reasons?

DKoor
06-28-2009, 04:03 PM
Yes.

For instance;

<pre class="ip-ubbcode-code-pre"> alt canopy closed canopy open
A6M2-21 SL 436 422
A6M2-21* 4500 529 513
</pre>

horseback
06-28-2009, 04:24 PM
Many air forces had a lot of 'experienced' (meaning 'old biplane drivers') pilots who were uncomfortable with the reality of enclosed cockpits. Italy had two monoplanes (MC 200, G.50) that were originally conceived with enclosed cockpits, but got revised to open cockpits after the pilots' incessant complaints.

Soviet fighters early in the war usually flew with canopies slid back or removed entirely because the original models used a thick cellophane instead of plexiglass which quickly yellowed in sunlight and accumulated scratches almost as fast. I cannot imagine preferring the cold of an open cockpit during a Russian winter unless the alternative was being blind to the sides and above.

RAF fighters in the Middle East and Malta often dispensed with plexiglass canopies as well because the sand blasting back from the prop scratched them to the point that you couldn't see through them rather quickly. Again, the heat issue doesn't apply; at lower alts, the blasting air into the cockpit is more like that of a convection oven than anything that might be thought of as cooling.

Many fighter pilots preferred to takeoff and land with the canopy open so that they could adjust their seats as high as possible for better vision, never mind the heat or cold.

Finally, the Japanese (among others) were plagued with unreliable radios for most of the war, and formations often had to rely on visual signals from the lead aircraft; these were easier to see if the canopy was slid back.

cheers

horseback

Wildnoob
06-28-2009, 04:54 PM
the A5M "Claude" (the Zero's predecessor figther for example), was the same thing. it was tried a enclosed canopy but find very little favor among the aviators.

I read a report of IJN ace Tetsu Iwamato, in a combat over China, in 1939, flying a A5M, that he was intercepted at an altitude of 5000 meters by enemy figthers. the standard atmosferic measure was adopted in the post war. with dry wheater the temperature would be 15 celcius degrees (sorry, I don't understand how to convert to the fahrenheit measure). the temperature would fall 2 celcius degrees at each 1000 meters. so be, according to wat I calculate it would be 5 degrees celcius of temperature at 5000 meters. this without account the wind and the fact you are in a plane moving very fast and the thermical feeling. must no be very confortable. I have a photo of a Japanese Ki-27 aviator with heavy fligth clothing. also read in a Ki-27 book I have that IJA pilot's also preffer fly with canopy opened, but logic that until a certain point. will post it as soon as scan it.

but backing to the A5M, it's maximum service celling is 9700 meters. but logic, longer of a pratical one and totally out of the context of the plane that was intended to be used at lower and medium altitude in most cases. but was thinking, climb to 9700 meters with a plane that have a open canopy and not heating system. the test pilot's with totally sure diserved a high condecoration, I can't imaginate how must be do this. http://forums.ubi.com/groupee_common/emoticons/icon_eek.gif

Wildnoob
06-28-2009, 05:37 PM
no, I must be CRAZY...

no way a person would survive just with clothing with a plane that has a open canopy until reach 9,700 meters of altitude. LOGIC that the pilot's where using eletrical heat suits, no doubt about it. it would have hypothermia otherwise.

for example, the B-17 and B-24 waist gunners used eletric heated suits. they normally fly at about 25,000 ft (7500 meters) and the temperature was about -30 negative celcius degrees, while the plane as also a heat system. but I are with a little doubt, because already see some models (like the own IL2 ones) with glassed waist gunner positions with the gun firing though wat I think it may be probably a plexiglass. this was adopted later, because know that early think that not, there's just open windows to maned the waist guns.

R_Target
06-28-2009, 09:55 PM
Navy pilots usually fly with canopy open during takeoff and landing for quick egress in case of upside down ditching. It could often be left open to cool off as they climbed.

Dave McCampbell would also crack open the 'pit to smoke cigarettes at 30,000 feet. I'm sure he wasn't the only one.

robtek1957
06-29-2009, 06:28 AM
@wildnoob

afaik the temperature falls approximately 1 degree celsius per 150 m.
so if there is +15 degree celsius on the ground one might experience about -18 degree celsius in 5000m.

Tully__
06-29-2009, 07:47 AM
Originally posted by Wildnoob:
...sorry, I don't understand how to convert to the fahrenheit measure...

F = 9C/5 + 32
C = 5(F-32)/9

AllorNothing117
06-29-2009, 08:11 AM
Well I flew on a hot day in England recently and It was absolutly roasting in the cockpit whilst on the ground and that was about 18-20ish degrees C I can't imagine what it was like in somewhere like okinawa. That said, once we got in the air the plane let in air through two little vents and it was plesenlty mild (2000 -4000 feet.)

Wildnoob
06-29-2009, 12:14 PM
Originally posted by robtek1957:
@wildnoob

afaik the temperature falls approximately 1 degree celsius per 150 m.
so if there is +15 degree celsius on the ground one might experience about -18 degree celsius in 5000m.

http://forums.ubi.com/images/smilies/blush.gif

thank you very much for had correct me!

damm, this one is unacceptable, how I could say that, how... http://forums.ubi.com/images/smilies/disagree.gif

Wildnoob
06-29-2009, 12:15 PM
Originally posted by Tully__:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Wildnoob:
...sorry, I don't understand how to convert to the fahrenheit measure...

F = 9C/5 + 32
C = 5(F-32)/9 </div></BLOCKQUOTE>

thank you very much also mister Tully! http://forums.ubi.com/images/smilies/25.gif

you guys are always saving me from my extreme ignorance. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif