mountain by cesZmr


									Mountain Flying
  How NOT to die…
Mountain Flying
            Mountain Flying
• Weather and Flight Planning
  – Downdrafts & Updrafts
  – Turbulence, Rotors, Wind Shear
  – Density Altitude
• Clearing Mountains
• Landing
• Ground Speed & TAS vs. IAS
             Mountain Flying
•   Takeoff Distance
•   Oxygen
•   Forced Landings
•   Course Reversal
•   Emergency Gear
•   Controlled Flight into Terrain (CFIT)
    Weather and Flight Planning
Mountain weather can change rapidly
  Check forecasts
  Contact Flight Watch (122.0) often
Colder temps  greater chance for icing
Fly early morning or late afternoon for
 lightest winds.
   Weather and Flight Planning
 VFR over high terrain may be impossible
  Even though your departure/destination
   airports are experiencing good weather.

Colorado Pilots Association recommends
 at least 15 Miles visibility.
    Weather and Flight Planning
Mountain flying is not a guaranteed go.
  Check the forecast, and then test the waters.
  If you like what you see initially, proceed;
  If not, turn back.
  Don't become too attached to completing
   your flight.
Don’t go if the weather is doubtful.
     Weather and Flight Planning
If stopping at multiple airports, use
 multiple flight plans.
  In general, if you’ll be stopping at multiple airports
   on a flight, it’s a good idea to use multiple flight
  If your plane goes down in between two airports,
   search crews will have a much better idea of where
   to look.
  If one leg takes a bit more or less time than
   planned, the clock is reset when you open your next
   flight plan.
    Weather and Flight Planning
Make sure you know the winds aloft and
 at your destination airports.
Try to plan your route so you are flying on
 upwind side of valleys and canyons.
Always know where the wind is coming
    Weather and Flight Planning
Rotors/wind shear are basically
 guaranteed at 20 kts,
  Especially on the lee side of a peak/ridge.
Use visualization to determine possible
 downdraft areas.
  Air behaves like water. Ask yourself, "What
   would water do if it were flowing like the
   winds aloft?”
    Weather and Flight Planning
The venturi effect in mountain passes can
 increase wind velocity significantly.
  This can produce winds in passes that are
   much stronger than winds aloft.
  Expect wind to be much greater velocity over
   mountain passes than reported in areas a
   few miles away.
    Weather and Flight Planning
 Winds aloft greater than 30 knots
 at cruise altitude usually means
 the novice pilot should delay or
 postpone the flight until more
 favorable conditions prevail.
    Weather and Flight Planning
When approaching a ridge:
  Inbound: fly at 45 degree angle when ¼ to
   ½ mile out
  Outbound: fly straight out (90˚ angle)
    get away as quickly as possible
  Downdrafts can be smooth or rapid/jolting
    Monitor the VSI
  A typical downdraft will produce a 1000 to
   1500 fpm descent
    Weather and Flight Planning
If caught in a downdraft
  Apply max power, Lean (for best power)
Do not pull up!
  It’s very common for people to pull up and
   then stall or enter a spin.
  People will often pull up and try to increase
   rate of turn by adding rudder.
  This is a perfect recipe for entering a spin at
   high altitudes.
    Weather and Flight Planning
Fly away at VA
  This may increase rate of descent, but it will
   get you out of downdraft as quickly as
  The further you are from a ridge, the less
   turbulence and downdrafts you will
    Weather and Flight Planning
Downdrafts on lee side of mountain 
 updrafts on windward
  If you get caught in a downdraft, look for an
   area where the wind may be rising.
  Find rising air and then perform shallow turns
   to remain in the updraft.
It may be necessary to fly toward a
 windward slope or some distance
 downwind before the aircraft can establish
 a positive rate of climb.
    Weather and Flight Planning
Most accidents caused by downdrafts are
 due to the pilot's concern about altitude
  Don’t try to out-climb a downdraft.
  Instead, try to escape away from the ridge
   that is causing the downdraft.
     Weather and Flight Planning
If lift (updrafts/downdrafts) is not a factor,
 fly on the appropriate side of the valley so
 that your 180˚ exit turn can be made into
 the wind.
    Weather and Flight Planning
Establish 2000 to 3000' clearance over
  Plan to cross mountains at least 2,000 feet
   above the highest point along the route.
  This altitude should be reached well in
   advance, as some terrain will rise faster than
   the aircraft climb rate.
    Weather and Flight Planning
Lenticular clouds = extreme turbulence
Mountain waves can extend for tens or
 hundreds of miles
In heavy turbulence, fly an attitude and
 accept altitude loss
  Don't over-stress the airframe
    Weather and Flight Planning
Don’t rely on cloud shadows for wind
  Expect the wind to be constantly changing in
   direction and velocity because of modification
   by mountain ridges and canyons.
Don’t fly the middle of a canyon.
  This places you in a poor position to make a
   turnaround and it subjects you to shear
  Fly on the downwind side of canyons to catch
    Weather and Flight Planning
If you need to make a tight turn slow
  Flying slower provides for a more reaction
   time and a tighter turning radius.
    Weather and Flight Planning
There are three important factors that
 affect air density: altitude, temperature,
 and humidity.
        Weather and Flight Planning
 Calculate density altitude before your flight.
     Density altitude is the altitude the airplane thinks it is at and performs in
      accordance with.
     High, hot, and humid conditions may raise the effective physical altitude of an
      airstrip to a performance altitude many thousands of feet higher than its actual
 Be familiar with the performance of your aircraft at altitude: service ceiling,
  takeoff and landing distance, climb rate.
     The horsepower output of the engine is decreased because its fuel air mixture
      intake is reduced.
     Normally aspirated engines lose about 3 percent of their horsepower for each
      1,000 feet above sea level.
     For a normally aspirated engine, the maximum power you can generate at 7500’
      is 75%.
     The propeller develops less thrust because the blades are less efficient.
     The wings develop less lift because the less dense atmosphere exerts less force
      on the wings as airfoils. As a result, the takeoff distance is increased and the
      climb performance reduced.
       Weather and Flight Planning
 Know the performance of your airplane:
    VY decreases with altitude.
        As a rule of thumb, subtract 1kt for every 1,000 feet of density altitude.
    VG decreases as weight decreases.
        As a rule of thumb, VG decreases 2kts for every 10% under maximum gross
 Weight and density altitude are the two most important factors
  when considering the appropriate airspeed to fly for best rate of
  climb or best glide.
    Learn to interpolate to figure the proper performance data before you
     need it.
 Don't use short field flap settings for high density altitude
  takeoffs (unless the field is truly short.)
    Short field flap settings offer a better angle, not rate of climb.
    At the typically long high-elevation airports flaps will be a hindrance to
     reaching VY more quickly.
    Weather and Flight Planning
A good way to compensate for lower
 power is to be light.
  As a rule of thumb, being 10% under
   maximum gross weight provides a 20%
   performance benefit over the POH numbers.
           Clearing Mountains
The visual aspects of mountain flying can
 be deceiving.
  but if you can see more and more of the
   terrain on the other side of the ridge you are
   approaching, you are higher than the ridge
   and can probably continue.
Plan every ridge crossing as though an
 engine failure was imminent.
          Clearing Mountains
 Always remain in a position where you can
  turn toward lowering terrain.
 This axiom also encompasses the idea that
  you will not enter or fly in a canyon where
  there is not sufficient room to turn around.
  Another way of stating this truth is to have an
  escape route in mind and be in a position to
  exercise this option.
                    • Sparky Imeson “The Mountain Flying Bible”
               Clearing Mountains
   Do not fly beyond the point of no return.
      This is the position when flying upslope terrain where, if you reduce
       the throttle to idle and begin a normal glide, you will have sufficient
       altitude to turn around without impacting the terrain.
      As you near the ridge, when arriving at a position where the power
       can be reduced to idle and the airplane will glide to the top of the
       ridgeline, a commitment to cross the ridge can be made.
      At this position, the airplane is close enough to the ridgeline not to
       experience an unexpected downdraft of a nature that will cause a
      If a downdraft is encountered, keep the power on, lower the nose to
       maintain airspeed and the airplane will clear the ridge.
                                         • Sparky Imeson “The Mountain Flying Bible”
           Clearing Mountains
Realize that the actual horizon is near the
 base of the mountains.
  This mistake of using the summit of the
   peaks as the horizon will result in the aircraft
   being placed in an attitude of constant climb.
  This could inadvertently lead to stall from
   which a recovery may be impossible.
Landing at a short mountain strip requires
 exact airspeed control to eliminate float.
  A 10% increase in the proper approach
   speed results in a 21% increase in landing
 Make sure to richen mixture for go-around
 Momentarily increase to full power when close to
  pattern altitude, but makes sure you have enough time
  to loose the airspeed you’ve gained.
   Richen to 50˚ – 100 ˚ rich of peak EGT.
      (50 ˚ is good for small engines, 100 ˚ good for high performance)
 Depending on your altitude, cruise power at high
  elevation is likely to also be maximum power.
   If this is the case, your fuel-air mixture is already properly set
    and requires no adjustment for landing.
 See your airplane’s POH for the manufacturer’s
  recommended leaning procedures.
"The most common problem for
 flatlanders is the tendency to fly the
 approach below the normal indicated
 airspeed for landing. Thus, an area of
 heavy emphasis for mountain flying is to
 fly by the numbers and approach to land
 at the normal indicated airspeed.“
                - Colorado Pilots Association
For safety from eddies, wind shear, and
 gusty conditions, plan your approach
 using the runway numbers as your aim
  Flare 500 feet down the runway, and try to
   touch down on the 1,000 ft. marks.
  High altitude runways are quite long and this
   provides insurance in case of a severe
Be certain to use the same indicated
 airspeed at high-altitude airports that you
 use at low-altitude or sea level airports for
 the takeoff or for the approach to landing.
When flying to remote airports, before
 landing, first overfly the field to check for
 wildlife and runway conditions.
If you haven’t landed by ½-way down the
 runway, you should abort the landing.
Runway Illusions:
  You’ll look high due to narrow runways
  Your eyes tend to focus on rising
    This will cause you to come in high if a hill is
     near the runway.
Sloping runways are common in
  This can create illusions of being too high
   (upside) or too low (downslope)
  The slope will also affect takeoff and landing
  This can be a very significant important factor
   at mountain airports.
Ground Speed & TAS vs. IAS
Roughly, the TAS increases by 2% over IAS
 for every thousand feet altitude gain.
  This implies that at 10,000’ the TAS will be about
   20% higher (if calculated accurately it’s actually
   closer to 15%)
  This is a built-in compensator for reduced lift
   caused by the thin air at higher altitude airports.
  Ground speed will be much higher, visual
   queues will be very different.
  Since TAS is higher, you’ll need to fly pattern
   wider than normal.
                Takeoff Distance
 Before landing at a mountain airport, make sure you
  can climb back out.
   One technique you can use is to overfly the field at, say,
    1500 feet AGL and apply full power.
      If you don’t achieve at least 300fpm climb rate, you probably
       shouldn’t land.
   A rule-of-thumb for operating from a short runway is that if
    you obtain 71% of the speed necessary for rotation at the ½-
    way point of the runway, you can take off in the remaining
      Calculate this speed beforehand and review it as part of your pre-
       takeoff briefing.
   E.g. VR=55kts - need to obtain 39kts at ½-way point.
   The ½-way point should be treated as a solid abort point.
             Takeoff Distance
Before takeoff, you must lean for max power
  For a plane with a direct drive engine and a fixed
   pitch propeller, before takeoff, hold the brakes,
   apply full throttle, lean to peak RPM (or 50˚ – 100 ˚
   rich of peak EGT).
    Leave mixture at that position and accomplish the takeoff.
  For a plane with a constant speed propeller, leaning
   is normally done using the EGT.
    See your POH for the manufacturer’s recommendation.
            Takeoff Distance
The takeoff distance varies with the gross
  A 10% increase in gross weight will cause:
    5% increase in speed required for takeoff.
    9% decrease in acceleration (from stop to takeoff
    21% increase in takeoff distance.
You may not want full fuel on takeoff from
 a high-altitude airport.
                 Takeoff Distance
 A good "rule of thumb" for the pilot to remember is -
  for each thousand feet above sea level, the takeoff run
  increases approximately 25 percent.
   In the case of normally aspirated engines (not turbocharged
    or supercharged), at an altitude of 10,000 feet, about one-
    half of available engine horsepower is lost.
      Example: Denver, Colorado: field elevation indicated on the
       altimeter is 5000 ft; Summer day 80˚F
         density altitude is 7500 feet
         the takeoff distance will be 2.3 times the sea level takeoff roll.
 The double whammy: not only must the airplane be at
  a higher true airspeed to achieve flying speed, but it
  must do so with an engine that's not capable of
  making sea level horsepower.
 Density altitude can be much higher than indicated
   The effect of altitude on your body depends on the partial
    pressure of oxygen.
   Note that altimeters show pressure altitude (corrected for
    local altimeter setting).
 The U.S. Air Force recommends using oxygen starting
  at 8000ft.
 FAA regulations
   No O2 required until 12500 (although not required, it is
   Between 12500 and 14000, after ½ hour
   Higher than 14000, continuous
   Higher than 15000, must be provided for passengers
 Night vision is inhibited above 5000’ pressure altitude.
 Cannulas can't be used above 18000'
    Manufacturers prohibit use above this altitude.
    Above this altitude, up to 25,000’ you can use an oxygen mask.
 Regulator and flow meters fail, valves freeze, and lines plug up,
  so always be prepared to descend.
    It may make sense, because of the increased risk, to plan a flight at, say,
     16,000’ vs. 22,000’.
 The time of useful consciousness at 20,000’ is 30 minutes
 At 22,000’, the time of useful consciousness is about 10
    Time of useful consciousness is sometimes also referred to as EPT, or
     Effective Performance Time.
Oxygen bottles are normally low pressure
  500 PSI, or high pressure
1800 PSI is the most common variety.
  The 1800 PSI bottles are green.
Oxygen bottles need to be re-certified
 every 5 years.
It is a good idea to consider oxygen for flights
 above 5,000 feet at night and above 8,000 feet
 during the day.
Use of pulse oximeter
 A general rule-of-thumb for using a pulse oximeter is
  to never let your oxygen saturation level get more than
  10 percentage points below your home (ground level)
  saturation level.
            Forced Landings
Don’t choose a route that would prevent a
 suitable forced-landing area
In the event of a forced landing, approach at
 best glide, but touch down / impact at stall
Don’t leave the airplane without a compelling
 reason if you have executed an emergency or
 precautionary landing.
  Temporary evacuation may be necessary if a fire
   hazard exists.
             Forced Landings
If you have a choice between landing in light
 green trees or dark green, head toward the
  Light green trees are more pliable, younger than
   dark green trees.
Don’t land in water.
  You’ll flip upside down and, since the plane won’t
   be visible, it’s less likely than you’ll be found.
  Also, mountain water is cold and you could contract
          Forced Landings
Follow roads whenever possible.
Avoid flying over open water (Lake Tahoe,
Plan your trip along routes that include
 populated areas and well-known passes,
 or over valleys whenever possible.
          Forced Landings
Follow roads whenever possible.
Avoid flying over open water (Lake Tahoe,
Plan your trip along routes that include
 populated areas and well-known passes,
 or over valleys whenever possible.
Swaths cut through trees are usually
 power lines. It’s usually best to avoid
          Forced Landings
 Learn how to turn it on.
 The ELT may not turn on automatically in a
  forced landing, so you may need to arm it
             Course Reversal
Everyone flying in the mountains will encounter
 situations when it becomes necessary to make
 a 180˚ turn.
  To turn around, slow down. This will decrease the
   radius of turn.
  Pull back on the control wheel to trade airspeed for
   altitude if you have extra speed.
  Then make the steepest turn you can comfortably
   make, up to 60 degrees.
To execute a course reversal in IMC and end
 up over the same spot turn 90˚ followed by 270˚
  an 80˚ /260˚ also works
                 Emergency Gear
   Warm clothes
   Blankets or sleeping bags
   Food
   Water
   Flashlights
   Fire starter
   Radio
   Signaling mirror
   Maps
   Compass
   Wear or bring shoes you can use for hiking

 Always bring emergency gear when flying in the mountains.
   Controlled Flight Into Terrain
Controlled Flight into Terrain (CFIT)
 occurs when an airworthy aircraft under
 the control of a pilot is inadvertently flown
 into terrain, water, or an obstacle with
 inadequate awareness on the part of the
 pilot of the impending disaster.
   Controlled Flight Into Terrain
 Accidents occur most frequently in GA operations
   4.7% of all GA accidents and 32% of GA accidents in IMC.
   On average there are 1.4 fatalities per CFIT accident, versus
    0.33 fatalities per GA accident overall.
 17% of all GA fatalities are due to CFIT
 CFIT accidents are fatal 58% of the time.
 CFIT accidents occur 64% of the time in daytime and
  36% at night
 51% of CFIT accidents occur in IMC, 48% in VMC and
  1% unknown.
 Impacted terrain was flat 45% and mountainous 55%.
      Controlled Flight Into Terrain
    NTSB Identification: DEN07FA054
    14 CFR Part 91: General Aviation
    Accident occurred Wednesday, January 17, 2007 in Centennial, WY
    Aircraft: Piper PA-28-180, registration: N43630
    Injuries: 3 Fatal.
•   This is preliminary information, subject to change, and may contain errors. Any errors
    in this report will be corrected when the final report has been completed.
    On January 17, 2007, approximately 2215 mountain standard time, a Piper PA-28-
    180, N43630, registered to Archer Nevada LLC, and piloted by a private pilot, was
    destroyed when it impacted mountainous terrain during cruise flight, 6 miles
    northwest of Centennial, Wyoming. Night visual meteorological conditions prevailed.
    The personal flight was being conducted under the provisions of Title 14 Code of
    Federal Regulations Part 91 on a visual flight rules flight plan. The pilot and his two
    passengers were fatally injured. The cross-country flight departed the Rock Springs-
    Sweetwater County Airport (RKS) approximately 2115, and was en route to Grand
    Island, Nebraska (GRI).
    Controlled Flight Into Terrain
• According to Blue Ridge Aeronautics, a flight school in
  Vacaville, California, the flight departed Nut Tree Airport
  (KVCB) approximately 1100 Pacific standard time. The flight
  was to travel to Grand Island, Nebraska, on the 17th and
  continue on to Chicago, Illinois, on the 18th. The pilot reported
  to the flight school that he intended to follow Interstate 80 for
  the entire flight.
  According to the airport manager in RKS, the airplane arrived
  approximately 2030 and obtained fuel services. The airplane
  did not arrive in GRI and an Alert Notification (ALNOT) was
  issued for the missing airplane. According to National Track
  Analysis Program (NTAP), the airplane was tracked from RKS
  to 10 miles west of Centennial. Search and rescue crews
  located the airplane wreckage approximately 0830 on the
  morning of January 19th.
     Controlled Flight Into Terrain
• The National Transportation Safety Board investigator-in-charge arrived on
  scene approximately 1300 on January 19, 2007. The accident site was
  located in mountainous, forested, snow covered terrain. A global positioning
  system receiver reported the coordinates of the main wreckage as 41
  degrees 21 minutes 58.6 seconds north latitude, and 106 degrees 15
  minutes 29.6 seconds west longitude. The accident site was at an elevation
  of 10,710 feet mean sea level and the airplane impacted on a magnetic
  heading of 260 degrees. The wreckage consisted of the fuselage,
  empennage, and the left wing. The right wing separated partially and was
  found adjacent to the belly of the fuselage. The wreckage came to rest
  inverted in approximately 3 to 5 feet of snow.
   The closest official weather observation station was Laramie Regional
   Airport (KLAR), Laramie, Wyoming, located 27 nautical miles (nm) east of
   the accident site. The elevation of the weather observation station was 7,278
   feet msl. The routine aviation weather report (METAR) for LAR, issued at
   0953, reported, winds, 290 degrees at 9 knots, gusting to 18 knots, visibility,
   10 statute miles; sky condition, clear; temperature minus 10 degrees Celsius
   (C); dewpoint, minus 18 degrees C; altimeter, 29.94 inches.
Controlled Flight Into Terrain
                     Further Study
 For Further Study
   Books by Sparky Imeson
      “The Mountain Flying Bible”
      “The Shirt Pocket Mountain Flying Guide”
          Order them here:
   "Hypoxia, Oxygen and Pulse Oximetry," Furgang, Fred, MD.
   Pulse Oximetry and the Oxyhemoglobin Dissociation Curve

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