Flying VFR in the Mountains

Take Five: Flying VFR in the Mountains

Flying VFR in the mountains calls for a few extras...

Flightplan for reduced power, prop efficiency and lift at the higher altitudes you’ll meet in the mountains:

  • the density altitude is the key
  • a lightly-loaded aircraft is best-but carry enough fuel

Carefully study the terrain beforehand so you’ll always know what’s ahead:

  • always use current charts and a valid Canada Flight Supplement (CFS)
  • choose common VFR routes
  • apply the right-hand rule in a valley for traffic separation and room to turn around
  • keep map reading enroute so you’ll always know exactly where you are
  • do not rely solely on GPS for navigation

Get a good weather briefing:

  • expect delays; a person in a hurry is a set-up to make the wrong decision to go
  • ask for, and pass along, pilot weather reports (PIREP)

Set your own visibility limits well above the regulated minima, and always be prepared to turn back when it becomes less.

Know where the downdrafts are likely to be-and stay away:

  • turbulence is a good signpost
  • air descending over downwind slopes can exceed an aircraft’s climb capability
  • daytime heating of a valley slope can generate a downdraft on the shaded side
  • constantly monitor your altimeter
  • stay away from the violent turbulence of mountain waves and rotor zones-know the warning cloud types

Beware of the valley trap:

  • study your charts ahead of time
  • get to a safe traversing altitude before entering a valley
  • keep at a safe height and avoid flying close to terrain
  • as the valley narrows or climbs, turn around before your airspeed starts falling

Remain alert for the false horizon illusion:

  • continually monitor your instruments
  • suspect an illusion whenever you’re surrounded by sloping terrain, i.e. when the horizon’s hidden
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