Inadvertent IMC Entry

I ran across the story about the Korean Air flight that crashed in Guam in the late ’90s the other day.  It was a 747 that hit the side of hill about 3 miles short of the runway, killing most of the people on board.  The flight was at night (arrival time was about 1:30am) and the pilot’s lost sight of the runway on a visual approach due to inadvertent IMC entry.  They didn’t execute a missed approach soon enough, got too low, and crashed.

Korean Air Crash

These were experienced pilots, mind you, who had flown into that airport a number of times. They were experienced enough to know when to execute a go around.  There were several other factors that led up to the crash, but, ultimately, they lost sight of the runway due to inadvertent IMC entry.

To all the VFR pilots out there, what do you do if you accidentally fly into a cloud?  It’s a lot easier to encounter inadvertent IMC at night, simply because you can’t see the clouds in front of you.  It is no less dangerous during the day, either.

So, we’re going back to the basics today.  What really is the best course of action for a VFR pilot when flying into a cloud?  One option (and in my opinion, the best option) is to turn around. Immediately start scanning your instruments, execute a shallow banked 180 degree turn while maintaining altitude, and fly out of the cloud you just flew into.  If you have an autopilot, turn it on immediately and let it do the turn.

What if you were descending or climbing when you encountered the inadvertent IMC?  In this case, just reverse whatever you were just doing.  If you were descending, climb.  If you were climbing, descend.  Caution is needed, though, as climbing or descending when flying on instruments for an inexperienced IFR pilot could lead to a greater chance of disorientation.

One thing that could assist in spotting those clouds at night is turning the cockpit lights down.  This will allow you to see outside a little bit better and start to notice when those ground lights are disappearing.

IMC FlightMost VFR pilots only do instrument flying on flight reviews.  That doesn’t lead to a very high level of proficiency, so go out and grab your instructor and tell him to put you under the hood once a month.  You’ll be a better pilot overall for it.

IFR pilots, taking a note from the Korean Air flight; if you lose sight of the runway on a visual approach, especially at night, go missed and ask for the instrument approach procedure.  Don’t try and duck down below the clouds as there may be a hill or a mountain directly below you.

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    I don’t. I verify the hole is clear and that’s about it.

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    The early -310P Malibus are pretty simple and straight forward. Move the vane, get the horn.

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    • If the oil temperature is between 100-125, skip the hot start, don’t prime the engine, and perform a normal start with the boost pump on
    • If the oil temperature is below 100, perform a normal prime and start

    Piper Malibu (PA46-310P with Continental Engine)

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      • Less than 125-150 degrees:  15 seconds
      • Less than 100-125 degrees, no need to run the Low Boost
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    • Magnetos:  On
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    Piper Mirage & Matrix (PA46-350P and PA46-350T with Lycoming Engine)

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      • Con is that if the engine doesn’t start on the first try, you are flooding your motor

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    • Throttle and Mixture Idle Cutoff
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    Beechcraft 36 Bonanza

    • Throttle and Mixture Idle Cutoff
    • Low Boost:  Run for 30-60 seconds.  Reference above temperatures on the non-turbo Cirrus for run times
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    Want to make it better than a Cirrus or a Cessna TTx?

    Meet the team at RDD creating the LX7.  Just make sure you are sitting down as you are about to be blown away.

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