Moderators: richierich, ua900, PanAm_DC10, hOMSaR
stratclub wrote:How does your watch register altitude? Could it be by GPS or other means or is their an actual altimeter in the watch? You watch may not be reading actual cabin BARO pressure to determine altitude. IIRC, When we did high altitude testing out of El Alto (La Paz), if the crew set the ECS (pressurization) landing altitude to field elevation, the oxygen masks would deploy.
GalaxyFlyer wrote:Usually the O2 system has a high elevation selection which raises the mask deployment to a higher value, usually a function of the FMS LDG ELEV
GF
stratclub wrote:How does your watch register altitude? Could it be by GPS or other means or is their an actual altimeter in the watch? You watch may not be reading actual cabin BARO pressure to determine altitude.
stratclub wrote:IIRC, When we did high altitude testing out of El Alto (La Paz), if the crew set the ECS (pressurization) landing altitude to field elevation, the oxygen masks would deploy on landing.
stratclub wrote:Is what I was referring to possible if the crew selected landing altitude manually and landing altitude set is within the range of deploying the masks?
GalaxyFlyer wrote:Usually the O2 system has a high elevation selection which raises the mask deployment to a higher value
GalaxyFlyer wrote:Any 787 pilots that might be able to run a runway analysis and range estimate out of LPB? It’s 5,000 nautical and about 10.6 hours great circle, so it might just be doable.
Also, LPB normally has an above standard barometer, reducing its pressure altitude.
GF
rjsampson wrote:stratclub wrote:How does your watch register altitude? Could it be by GPS or other means or is their an actual altimeter in the watch? You watch may not be reading actual cabin BARO pressure to determine altitude. IIRC, When we did high altitude testing out of El Alto (La Paz), if the crew set the ECS (pressurization) landing altitude to field elevation, the oxygen masks would deploy.
Many smartwatches carry pretty effective altimeters. That said: you can't set the ambient baro from 29.92 so the actual cabin altitude could have been lower than your watch suggested, hence no deployment of oxy masks.
ClipperYankee wrote:I seem to remember LH flew 747s out of LPB and they would rumble down the runway for what seemed like five minutes before they could get airborne? I don't know if they flew non-stop to Europe or made a fuel stop somewhere though, I would guess they stopped.