Aerosoft Aerosoft Team [Inactive Account] 51558 Posted February 1, 2012 Aerosoft Share Posted February 1, 2012 see this? That was mid Siberia yesterday.... That's some serious high pressure. If you don't set you altimeter right you would be in for some serious surprises. Thanks to Stefan for the tip. Link to comment Share on other sites More sharing options...
Aerosoft Aerosoft Team [Inactive Account] 51558 Posted February 1, 2012 Author Aerosoft Share Posted February 1, 2012 Just found out that 1085 is the record, somewhere in Mongolia Link to comment Share on other sites More sharing options...
hals1010 41 Posted February 1, 2012 Share Posted February 1, 2012 Isn't low pressure (<< 1013 hPa) more dangerous? I mean, in these conditions you assume that you are higher than you really are... Link to comment Share on other sites More sharing options...
Aerosoft Aerosoft Team [Inactive Account] 51558 Posted February 1, 2012 Author Aerosoft Share Posted February 1, 2012 Isn't low pressure (<< 1013 hPa) more dangerous? I mean, in these conditions you assume that you are higher than you really are... Well yeah, but starting the flare at 1300 feet AGL is not advised.. 2 Link to comment Share on other sites More sharing options...
Stefan Hoffmann 4160 Posted February 1, 2012 Share Posted February 1, 2012 Yeah, when i think about setting not to fresh QNH on approach freshly it ends (VFR, bad sight): 1. with very high pressure: overshoot 2. very low pressure: Taste of runway threshold soil Link to comment Share on other sites More sharing options...
Aerosoft Aerosoft Team [Inactive Account] 51558 Posted February 1, 2012 Author Aerosoft Share Posted February 1, 2012 But it does make some remarkable low landing speeds (of course in ground speed as indicated air speed will remain the same). Those who got the flight calculator we gave out for free recently can find out very easy! Link to comment Share on other sites More sharing options...
EDNR-Cruiser 319 Posted February 1, 2012 Share Posted February 1, 2012 ...and combined with the current OAT your old Cessna 172M feels more like a turbo-charged 182! Geeze... At 55 kts IAS the old bird didn't just rotate, it JUMPED into the sky and climbed with 1,200+ ft/min! I felt almost like in an elevator... - had to force the baby down in the end! Unbelievable! Link to comment Share on other sites More sharing options...
Chris_327 42 Posted February 1, 2012 Share Posted February 1, 2012 Flying RW today, QNH passed from the tower was 1037. Highest I've seen, apparently last winter it got to 1049 over here! Link to comment Share on other sites More sharing options...
Deputy Sheriffs mopperle 4162 Posted February 1, 2012 Deputy Sheriffs Share Posted February 1, 2012 BTW the world record is 1083.8 hPa messured 31. December 1968 in Agata (263m a. MSL) in the northwest of Siberia. On 20. January 2010, there was a value of 1086 hPA reported in Mongolia. But it was not accepted due to the height of the locations (1421m and 1928m a. MSL) and the therefore resulting errors. Link to comment Share on other sites More sharing options...
kaspis29 29 Posted February 1, 2012 Share Posted February 1, 2012 We had (and still have) very high pressure here in Latvia, Monday it climbed to QNH1053, the funny thing is that the Fokker50's which are operated by airBaltic (about 9) is limited to QNH1051 (As I was told) Link to comment Share on other sites More sharing options...
Aerosoft Aerosoft Team [Inactive Account] 51558 Posted February 1, 2012 Author Aerosoft Share Posted February 1, 2012 We had (and still have) very high pressure here in Latvia, Monday it climbed to QNH1053, the funny thing is that the Fokker50's which are operated by airBaltic (about 9) is limited to QNH1051 (As I was told) I know there are more aircraft that can't go over 1051 while the FS models can. Try buggin that to the developers! And yes we checked, as far as I know all the aircraft I am responsible for are okay, lol Link to comment Share on other sites More sharing options...
EDNR-Cruiser 319 Posted February 1, 2012 Share Posted February 1, 2012 Mathijs, being better than the original still isn't realistic! Link to comment Share on other sites More sharing options...
Deputy Sheriffs Herman 1591 Posted February 2, 2012 Deputy Sheriffs Share Posted February 2, 2012 Here in the U.S., we have an FAR (Federal Aviation Regulation) that requires special procedures when the pressure exceeds 31"Hg (or, using my terrific Aerosoft calculator, 1049.77 hPa). Here it is: FAR 91.144 Temporary restriction on flight operations during abnormally high barometric pressure conditions. (a) Special flight restrictions. When any information indicates that barometric pressure on the route of flight currently exceeds or will exceed 31 inches of mercury, no person may operate an aircraft or initiate a flight contrary to the requirements established by the Administrator and published in a Notice to Airmen issued under this section. (Waivers. The Administrator is authorized to waive any restriction issued under paragraph (a) of this section to permit emergency supply, transport, or medical services to be delivered to isolated communities, where the operation can be conducted with an acceptable level of safety. VNAV procedures can also be affected, although this is rare. Temperature limitations (in my experience) are typical. Look for "BARO-VNAV" limitations in the plan view. A search on the net with a good engine will point you in the right direction. Poster 3 asked if lower pressure was more dangerous. Each has it's own hazards. For a given set of conditions save pressure, higher than standard pressure equals lower pressure altitude which equals lower density altitude which equals better performance. The converse is of course true, and no one likes lower performance. However, as you fly into an area of lower pressure from one of higher pressure, altimetery errors increase. Hence, the saying, "High to low, look out below." Setting the correct QNH helps (close to the airport) but doesn't eliminate the error. 2 Link to comment Share on other sites More sharing options...
Aerosoft Aerosoft Team [Inactive Account] 51558 Posted February 2, 2012 Author Aerosoft Share Posted February 2, 2012 Good post Herman Link to comment Share on other sites More sharing options...
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