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Wildnoob
02-05-2009, 04:39 PM
hello folks!

I'm with a strange doubth about the BF-109 and the variometer. there's any special reason to the plane didn't have a variometer until the K series ?

the variometer is very usefully for trim the plane or when you are into cloud cover and need to know if the plane is neutral, loosing or gain altitude for example. I say that because planes of it's time like the I-16 have this instrument. the FW-190 also since it's introduction. this is wat I think that is a bite strange. if someone can give me this information in a few words I would be glad. though I are already much glad for anyone who just acess this topic. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

stalkervision
02-05-2009, 05:45 PM
which is it? http://www.luftarchiv.de/bordgerate/cockpits/bf109e7a.jpg

TX-EcoDragon
02-06-2009, 04:20 AM
The VSI is more of a performance instrument than anything else. . .sure it helps plan when, and how steeply to descend to reach airport/pattern altitude from a certain distance and altitude etc, but it’s non-critical. In maneuvering flight, you will pretty much never look at it. In steady state flight, the altimeter gives a more instantaneous indication of any altitude deviation than the VSI does (in the real world) if the pilot intends to maintain a constant altitude. In a climb where maximal climb performance is sought, a climb will be made at the best rate of climb airspeed, where the airspeed indicated is primary for pitch. Certainly a VSI is useful for a “constant rate climb/descent”, but this is minimally useful in a combat environment. In some designs that aim for the highest performance, extra weight is counter to that goal (it all adds up) so if it's not needed, it's not there.

Wildnoob
02-06-2009, 05:35 AM
thank you very much folks!

it was just curiosity from my part. now my doubth is solved. http://forums.ubi.com/images/smilies/25.gif

LovroSL
02-06-2009, 06:50 AM
also- where is the artifitial horizon in early bf109's? clouds are a bit http://forums.ubi.com/images/smilies/sadeyes.gif in this bird

maybe in RL you could "feel" how is the plane oriented?

TX-EcoDragon
02-07-2009, 12:08 AM
Originally posted by LovroSL:
also- where is the artifitial horizon in early bf109's? clouds are a bit http://forums.ubi.com/images/smilies/sadeyes.gif in this bird

maybe in RL you could "feel" how is the plane oriented?

No, you can't feel the attitude of the aircraft. . .it generates it's own gravity as a result of the accelerations of flight. Consequently you can be in any attitude, and still feel as if you are upright. This is why Gyros are used as they attempt to maintain rigidity in space, and this is independent of "gravity". There were people that thought that they could use a water jug to keep upright in clouds. . .if they survived, they no doubt had a different opinion after the attempt. For a visual example as to why a fluid doesn’t know any better than you do (in fact your sense of motion is fluid based as well, and prone to the same errors), watch this video: http://www.youtube.com/watch?v=Xp2Uc9XvmjY

In aircraft that lack an attitude indicator/artificial horizon when entering clouds keep "the ball" centered, and use the turn needle of the same instument to indicate a constant indication of turn or straight up to maintain a level attitude. This is challenging in turbulence or after a flight upset, but still possible, and how “IFR” flight was often done in the olden days, and today too (though usually in an emergency).