Daniel Neugebauer Posted July 31, 2022 at 11:18 AM Posted July 31, 2022 at 11:18 AM I am a bit confused about the requirement to use real-world temperatures in the latest CoC revision posted in Quote New Section B13: Pilots are encouraged to utilize current real- world weather at all times. Pilots must utilize at least the following current, real-world weather parameters throughout all phases of flight: (a) Winds, (b) Pressure, (c) Temperature I am not sure about the intentions and implications of the CoC requirement to use actual temperatures that would be observable over the network: Regarding temperature effects on altitude: At temperatures below ISA pressure altitudes get lower to actual ground/geographic altitudes (altimeters read a wrong higher-than-actual altitude) and vice versa. Simulators have only recently started to simulate those, most notably MSFS2020. Other simulations already supporting it are PSX and the HotStart Challenger in X-Plane 11. X-Plane 12 will also simulate that effect. Previously, the temperature effect has been compensated (MSFS with vPilot) or disabled (Challenger XP11) when flying online, so the effect should only be observable over the network if the effect is actually leaked which has been intentionally avoided so far to establish compatibility with clients stuck at ISA conditions. Does the new requirement mean those compensations should no longer be active and uncompensated temperatures should be transmitted to VATSIM? What about older simulators always simulating ISA conditions? Those would basically violate the CoC whenever real-world temperature does not match ISA as they would fly at "wrong" altitudes. Impact on cold-weather operations: Unless the aircraft addon simulated and thus required it (FSLabs Airbusses, HotStart Challenger) most people did not ask for deicing when it would be needed by real-world safety regulations and SOPs. If we are asked to apply real-world tempatures, does that also mean we should from now on request deicing regardless of whether its required by the simulation we use? Engine performance: While performance depends on outside air temperature, airliner pilots usually apply engine derates. This means that the observable temperature effects on engine performance are probably very small, if at all noticeable. 2 Link to comment Share on other sites More sharing options...
Alistair Thomson Posted July 31, 2022 at 06:18 PM Posted July 31, 2022 at 06:18 PM 6 hours ago, Daniel Neugebauer said: actual ground/geographic altitudes There is no such thing! References to distances from ground are heights. The pressure settings given by ATC automatically take pressure variations due to deviation from ISA into account (except of course for flight levels). So altimeters set to an altitude pressure setting are not wrong.:) Alistair Thomson === Definition: a gentleman is a flying instructor in a Piper Cherokee who can change tanks without getting his face slapped. Link to comment Share on other sites More sharing options...
Jonas Eberle Posted September 25, 2022 at 07:05 PM Posted September 25, 2022 at 07:05 PM With XP12 beta now out, this can be observed now in radar clients. As far as I understand it, any ISA temperature deviation will lead to reported non-ISA altitudes/FLs. (The current 12.00b4 actually is not able to reproduce > FL100 because it has a general bug with high altitude weather) Link to comment Share on other sites More sharing options...
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