I used to fly a lot of single engine, real instruments flights. The=20
preflight check for pitot heat was simply to observe the ammeter while=20
switching it on/off.
An instrument pilot is expected to have a good idea about what the=20
airspeed is for a given power setting at a given altitude in level=20
flight. The Pitot source affects only the airspeed indicator.
While needle, ball and airspeed are considered adequate to fly on=20
instruments, the Altimeter is the secondary (backup) airspeed indicator.

On 3/14/2014 7:00 AM, BOB wrote:
> The heaters in pitot tubes fail.  We used to check them on every pre and
> post flight inspection.  But then we could reach them from the ground
> without stands or ladders.

--=20
John Ferrell W8CCW
"Kindness is the language the blind can see and the
deaf can hear." - Mark Twain


--=20
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