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Ins and Outs of Safe Mountain Flying Adventures. Scott Stauter FAA Gold Seal CFII, MEI, AGII. Reference: Mountain Flying Bible Sparky Imeson. Why are Mountain checkouts necessary?. Aircraft performance suffers More severe/changeable/local weather Airports may not be as developed
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Ins and Outs of Safe Mountain Flying Adventures Scott Stauter FAA Gold Seal CFII, MEI, AGII Reference: Mountain Flying Bible Sparky Imeson
Why are Mountain checkouts necessary? • Aircraft performance suffers • More severe/changeable/local weather • Airports may not be as developed • Suitable landing spots are less available • Plan to survive an off-airport landing • Oxygen requirements • Careful preflight planning is necessary • Filing a flight plan is good insurance • Flight hazards
Aircraft Performance Suffers High Density Altitude means: • Less engine power (less oxygen molecules) • Less propeller thrust and less lift • Lean non-turbo for best power before Takeoff • Use Aircraft POH or AFM performance tables • With Density Altitude: • TAS higher than IAS, ~2%/1,000 ft • Groundspeed may be 20% faster (10,000 ft) • Vspeeds change: • Vx goes up ~0.5% /1000 ft • Vy goes down ~ 1 knot/1000 ft • Vx = Vy at absolute ceiling • With Gross Weight: • For each 100# below MGW • VA (turbulence) drops ~2 knots • Vs decreases ~1 knot • Takeoff Roll Increases with: • Higher density altitude • Tailwind component / local terrain effect • Rough or soft runway surface
Weather Challenges in Mountain Flying • Thunderstorms (3 phases) • Cumulus: storm building, good source of lift • Mature: rain and/or hail, updrafts & downdrafts • Dissipative: mostly downdrafts, clouds more transparent • Frost, ice, & snow must be cleared from airfoils • Aircraft performs according to Density altitude • Air density decreases with altitude • Hot air less dense ~600 ft/ 100F • Mountain waves Lenticular clouds (rotors) • Localized weather In a valley, near a body of water • Downdrafts on lee side of mountains Try to visualize where to expect • Turbulence Light, moderate, severe, extreme NOTAMs – give PIREPs (122.0) and use them
Airports may not be as developed • May not have any weather reporting • TRK and BLU have AWOS/ASOS • You may get nearby Wx by monitoring 122.8 • Over fly runway • Look for wildlife • Check for runway slope • Evaluate surface conditions: may be unpaved, grass or rough terrain, humps and dips, snow removal? • Approach • May be one-way in, other way out • May require non-rectangular approach • May have optical illusion (high or low) • Plan your Abort/Go around point (half runway) Weight needs to transfer to wings, or Abort • Departure • May require a turn immediately after takeoff • May have drop off at runway end • May not have runway snow removal
Suitable landing spots are less available Be aware of Emergency Landing Areas • Highways – watch out for powerlines and traffic • Rivers • Reservoir or lake shorelines • Mountain meadows are more rugged • Swaths cut through trees = power lines • High cruise altitudes give better gliding range • Logging roads usually narrow and winding • Small trees are better than big ones (ouch!) • Accessibility for rescue – near road Develop a where can I set down awareness
Plan to survive an off-airport landing Survivable emergency landing techniques • Psychological hazards • Reluctance to accept situation • Desire to save aircraft • Undue concern about injury • Concepts of crash safety • Maintain integrity of aircraft cabin area • Avoid body contact with interior structure • Energy absorption, use aircraft structure and vegetation • Occupant restraint • Groundspeed and stopping distance • Control sink rate – flare uphill • Survival equipment • Water, and signaling capability
Oxygen requirements • Breathable Oxygen Required • Pilot and Crew >30 minutes >12,500’ must use O2 • Pilot and Crew >14,000’ any time must use O2 • Available for passengers >15,000’ • Psychological training available at Beale & Edwards AFB • Altitude Chamber test • Experience hypoxia in controlled environment • Less O2 partial pressure at altitude; pulse oxymeters are useful • Hypoxia symptoms • Significant loss of vision • Anxiety • Headache • Nausea • Slow thinking and reflexes • Dizziness • Numbness fingers, nose & mouth • Fatigue • Blurred vision • Impaired judgment • Subtle personality changes • Cyanosis • Mental Confusion • Loss of consciousness • Hyperventilation can have similar symptoms • Caused by exhaling excessive CO2 • Usually triggered by stressful situations
Careful preflight planning is necessary • Start with standard weather briefing • Get the latest up-to-date weather for the route • Check the winds aloft, ask about any NOTAMs • You may have to call the destination airport,or someone nearby – sheriff’s department may be helpful • Plan for plenty of fuel reserves • You can have too much fuel (weight) • Sometimes fuel isn’t as available in mountains • AFD may show fuel services but it may not be available to “outsiders” • If density altitude is too high, depart before the heat of the day or after • Night falls quickly in the mountains -- Low altitude night flying not recommended • I require at least 300 fpm climb capability (light twin?) • Make your Go/No go decision • Never be under pressure to go • If you have any nagging doubts – Don’t go • Better to be on the ground, wishing I was in the air, than vice versa
Filing a flight plan is good insurance • Flight Plans are not required in the US • But if you file and open one, you must close it • Avoid “round robin”; delays search and rescue • Filing flight plan is Required in Mexico • But you don’t have to close – no search & rescue • I think search and rescue is a good thing • But they have far too many false alarms • So I developed a gimmick to prevent forgetting • I rotate my watch when I open a flight plan • If my watch is backward, my flight plan is open
Flight Hazards • Try to fly 2,000 ft above ridge lines • Never fly in Marginal VFR in the mountains • Actual horizon near the base of the mountains • Cross ridges at a 450 angle to the ridge line • Position aircraft where it can be turned toward lower terrain • If caught in strong downdraft, it may be best to point nose down and accelerate away • Never fly down the center of a canyon • There is often wind shear in the middle • You would give away half your turning radius • Fly near canyon wall if necessary to get updraft • Course reversal may be necessary e.g. Box Canyon • I teach a modified wingover: • Pitch up ~ 200 • Full throttle • Full flaps once IAS in white arc • Briskly establish steep bank • You can use elevator to quicken turn • You can drop the nose at 900 into turn