b17 carb heat and air filters

[ebbsy1]

hi i was doing a flight into Montreal temp was -7 c and i had the co pilot controlling the rpm cowl flaps. i was on approach and got the message that i was stalling while doing 130 knots.my question is is there a way to raise the carb temps while on approach.also ive noticed a message in the cockpit saying airfilters must be switched off above 15000ft and switched on bellow 15000ft but with the aid of the copilot turned on i get told to switch off above 8000ft to avoid overworking the turbo so not sure what the correct procedure is there.

[AviationAtWar]

Leave your turbos up at 8 and pull power back with the throttles rather than the other way around. The turbos will provide a little heat.

[ebbsy1]

thx for the reply,i think thats what i did but ill try it again see if it works,just trying to figure out if theres some other way of raising the carb heat when temps are low on approach and the outside temp is freezing.ill try control rpm my self manually see if thats helps or maybe turn turbo up to 10

[Tomas Linnet]

Turbo selector should be at "8" ("7" for 91 octane fuel)., if you have to go around there's a high risk of applying to much power.

[ebbsy1]

still learning the aircraft,so your saying never set at 10. im not sure on what grade oil to use yet for hot and cold weather i flew aroung the uk from humberside to newcatle down to isle of white back up to humberside,next day i flew to shannon airport island then onto canada were i went to bed and left the flight running overnight woke up and landed. im currently at reagan air port washington using real world weather and not changed the oil setting once average weather s been about -3 so far and ive gone through 2 sets of landing gear lol but the engine appears to be fine
thx for the reply

[Tomas Linnet]

have a look in the manuals