35k a side installed. For both, that's a sweet Mooney.



I'm told by some guys that using the heat causes the delamination that eventually causes these windows to need replacement, so only turn them on when you encounter or expect icing conditions. On the other hand, I'm told by some guys that you have to turn them on or they get "brittle" and crack.

Which is it?

Thank you for reminding me not to buy anything pressurized

I have mine on low on all flights except at lower altitudes when temps are above 20 C anyways.

Have never needed the high setting.

I was also told that low power helps the windshield flex.

My standard heats go on before entering the runway. 5 switches in the Mu2: Pitots, Statics, Windshields. They are thermostatically controlled so in summer they will cycle on and off as needed.

I prefer the constant regimented simple procedure and all the pilots in our plane do the exact same thing every time (in general theory).

I will prefer a relatively constant temperature through the flight vs a change.
They are treasured gems... nobody touches them. No line guys ever clean them.

And if you put your iPad or sunglasses on the glareshield I'm chucking them into the back seat.

Windshield heat low when taking the runway. Per the SFAR required checklist. The heat supposedly strengthens them anyway.

In many airplanes the heat is required to pass bird strike certification.

With heat the window can absorb a larger impact.

Craig,

Keep them heated. We had to replace a set in 1998 on the MU-2. One of the outter panes cracked on landing. The big issue is moisture getting to the plastic sheet between the panes. The current set still look like new, no de laminations anywhere.

BTW factor in an interior refit as you might as well do one when you replace the windows, as everything has to come out to gain access.

Regards,
Nigel

Thanks gents. I'll keep them hot. The interior and windshields were both very recently replaced, I just want to keep them in good shape. Eating a bird at 250 indicated or landing and cracking a window don't sound like great ways to do that.

I was told to turn them on , on the ground and not in flight as this may case them to shatter in flight .