Page 28 - Feb 24

I have written articles on windshields and windshield heat for this magazine. See “Windshields 101” in the Mar/Apr 2010 issue [Volume 4, Number 2] and “More on Windshields” in the April 2015 issue [Volume 9 Number 4]. Send me an email if you can’t find them.
Fuel Vent Heat: These are the tubes on the bottom of the wings just outboard of the nacelles. They tend to erode on the leading edge and sometimes the fine wires come unglued causing failure to heat. With the battery on, feel the tubes for heat but be careful not to burn your fingers. If it doesn’t get hot, add it to your squawk list.
Pitot Heat: As long as you are checking your fuel vents, you might as well check your pitot tubes. Just remember to take the pitot covers off before flipping that switch or you will have a big, melted mess on your hands! Believe me, I’ve done it myself and it’s a miserable experience.
There is nothing worse than having a routine and minor check turn into a major fiasco in a matter of seconds. My preventative measure is to take the pitot covers off and put my cell phone and car keys on top of them. This ensures that I put the covers back on when I’m done and I don’t get distracted by my phone while focusing on the aircraft.
Stall Warning Heat: On King Air 200s, 300s and 350s the stall warning vane only gets half heat on the ground because the squat switch reduces the heat to compensate for lack of airflow. On those models, if the tab gets warm, but not hot, you are good to go.
Stall warning heat on the model 90s is completely different. Its stall warning heat systems vary from aircraft to aircraft. It requires maintenance manual research by aircraft serial number to ascertain what configuration your 90 has. Suffice it to say, some 90s heat the vane all the time and others cycle the heat on and off. Allow ample time for heating in case yours is on a cycle, but don’t just go up and grab it. You could burn your fingerprints off! Especially if your stall warning heats continuously.
If a couple minutes have gone by and you haven’t blistered your fingers, add stall warning heat to your squawk list. And while you are at it, make a note for your shop to research what kind of stall warning system is on your 90.
Prop Heat: Although the prop heat boots are an external heat item, you are better off checking this in the air. The manual check done on the ground takes two people – one to turn the prop and feel the prop boots
26 • KING AIR MAGAZINE
FEBRUARY 2024