The danger of assumption

What indicated airspeed do you normally rotate at? (no real answer, just
curious) Take off with the twin requires us to hold it onto the runway
until 80mph, we definately do not want to rotate prematurely in case of an
engine failure.

We usually start to rotate (and that's not really what we're doing -- more
like applying mild back pressure) around 70 mph -- but that's not a hard and
fast figure. It all depends on "feel", in my experience -- which, in turn,
is based on weight, wind, temperature, etc.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Jay Honeck" wrote

We usually start to rotate (and that's not really what we're doing -- more
like applying mild back pressure) around 70 mph -- but that's not a hard
and
fast figure. It all depends on "feel", in my experience -- which, in
turn,
is based on weight, wind, temperature, etc.

Ground fog forms because the ground is cooling the air near it (due to
radiational cooling) faster than the air further from it. You already knew
that, though.

MY guess what happen, is that after you started to rotate, the warmer air
above started getting pushed down into the cooler air, warmed it up, (or you
got into the warmer air) gave you less lift than the cool ground air, then
you started not lifting so good. Just a guess, though.
--
Jim in NC

MY guess what happen, is that after you started to rotate, the warmer air
above started getting pushed down into the cooler air, warmed it up, (or
you
got into the warmer air) gave you less lift than the cool ground air, then
you started not lifting so good. Just a guess, though.

Man, that would require a layer just a few feet thick -- is that possible?

Actually, I know it is, as I've seen it at altitude. I suppose it can form
close to the ground, too, in a calm wind.

Strange how I can study weather in college, I can observe it carefully for
years, and I can spend so much time in the air -- and yet not understand it
very well at all.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Man, that would require a layer just a few feet thick -- is that possible?


Yep, we get it here often. You can stand in it and your head will stick
above it and your feet will be below it. Pretty freaky.

Jim