Aviation Rules of Thumb

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Aviation Rules of Thumb

• Checked Out From The SAFE Members Only Resource
  Center
• Society of Aviation and Flight Educators
   www.safepilots.org
•  

• John Mahany, ATP/MCFI
• Flight Advisor, EAA Chapter 7
• FAASTeam Lead Rep, KLGB
• September 13, 2011

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ATA SmartBrief, 8/30/11

• Automation prompts safety officials' concern
  about pilots' skillsAirplanes are become
  increasingly automated, leading some safety
  officials to raise concerns that pilots might be
  losing their in-flight instincts, which could be
  troublesome when faced with an issue. Rory Kay,
  co-chairman of the Federal Aviation
  Administration's committee on pilot training and
  an airline captain, says that the industry is
  suffering from "automation addiction," which is
  leading to different types of incidents.

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ATA SmartBrief, cont.

• "We think the best way to handle this is through
  the policies and training of the airlines to
  ensure they stipulate that the pilots devote a
  fair amount of time to manually flying," said
  Paul Railsback, operations director at the Air
  Transport Association. "We want to encourage
  pilots to do that and not rely 100 on the
  automation. I think many airlines are moving in
  that direction."

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More on piloting skills

• The ability of pilots to respond to the
  unexpected loss or malfunction of automated
  aircraft systems "is the big issue that we can no
  longer hide from in aviation," said Bill Voss,
  president of the Flight Safety Foundation in
  Alexandria, Va. "We've been very slow to
  recognize the consequence of it and deal with
  it."

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Some Aviation Rules of Thumb

• Navigation reciprocals
• Normally aspirated Turbo-charged
• Density Altitude
• Takeoff Performance
• Crosswind Component
• Vx Vy
• Cruise Climb

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More Aviation Rules of Thumb

• Flight Planning ISA
• Figuring TAS
• Figuring Va
• Engine Failure
• Converting KTS to MPH
• Maximum Glide
• Icing, weather, descent planning
• Your own?

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Navigation reciprocals

• Take the 1st digit plus two, 2nd digit minus two
  or visa versa
• Minus two, plus two
• 180 becomes 360
• 090 becomes 270

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Related accident?

• Lexington, KY CRJ takeoff accident,
• Aug. 27, 2006
• Did they brief the takeoff??
• Were their Heading Bugs properly set?
• They did not realize they were on the wrong
  runway until it was too late, at rotation.

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Comair 5191 CVR

• Pilot Thrust SetPilot That is weird, No
  LightsPilot YeahPilot 100 KnotsPilot
  CheckPilot vee onePilot RotatePilot Whoa!

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Generic Takeoff Briefing

• Departing KSNA or any other confirm R/W _ _
• If applicable, r/w is _ _ _ _ ft. long
• Density Altitude if applicable, is _ _ _ _
• Takeoff weather/visibility is X T/O alternate?
  
• Up to Vr, will abort for _ _ _
• Once airborne, if engine fails then _ _ _
• Any noise, DP or terrain issues?
• In event of emergency return, plan is ??

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Normally aspirated engines

• A normally aspirated engine only produces rated
  Hp at Sea Level on a Standard Day, or ISA 15C
  or 59F
• It loses 3 ½ - 4 hp for each 1000 increase in
  altitude.
• Every 10 deg. F/6C above ISA results in 1 less
  power output

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Turbo-Charged Engines

• Takeoff fuel flow
• Your takeoff fuel flow should be at least 10
• of your max rated hp. ie., for 285hp, expect
• 28.5 gph 310hp should be at least 31.0gph
• For turbo-normalized (8.5-1) it should be
  somewhat less
• CHT during takeoff/climb should be lt 380F
• Source, Mike Busch, Savvy Aviator

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Density Altitude

• For every 10F above ISA, add 600 to
• the airport elevation to figure density
• altitude and your airplanes performance.
• source, Richard L. Collins

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Density Altitude

• From AOPA Safety Advisor 6,
• Mastering Takeoffs and Landings
• the simple act of taking off or landing
• accounts for 50 of all general aviation
• related accidents

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Big Bear City, CA, takeoff - 6748 msl

• What is your density altitude?
• What is your takeoff performance?
• Do you know how to lean for takeoff?
• Begin the takeoff roll, and with full power, lean
  the mixture until there is some roughnesss, then
  enrichen until it runs smoothly.
• source, Mountain Flying Bible

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Takeoff performance

• T/O distance increases 15 for each 1000
• Increase in Density Altitude above S.L.
• A 10 change in aircraft weight will result in a
• 20 change in the takeoff distance required
• source Mountain Flying Bible

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Takeoff flap setting

• If you want to use flaps for takeoff, but there
  is no reference in the P.O.H., suggest turning
  the yoke full scale, either direction and lower
  the flaps to approximately match the down aileron
  deflection.
• source, Mountain Flying Bible

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Takeoff performance

• Short field takeoff advice from the late Sparky
  Imeson, noted mountain flying expert
• If you have not reached 70 of your takeoff speed
  ½ way down the runway, ABORT!
• Also, make sure the parking brake is OFF! ?
• source, Mountain Flying Bible

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Crosswind component

• The 5, 7, 9 rule
• Runway numbers are magnetic ATIS/ASOS
• winds are magnetic
• If the wind is 30, 45 or 60 degrees to the R/W
• Take 50, 70 or 90 of the wind velocity this
  becomes the direct crosswind component.
• Note Crosswinds are not hard limits they are
  only demonstrated more importantly, how is
  your cross-wind proficiency?

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Vx Vy

• Both Vx Vy decrease 1 knot per
• 100 pounds below max gross weight
• Verify this in the P.O.H.

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Cruise Climb speed

• Vy Vx C. Add C to Vy, this is cruise climb
• Ex., a CE 172S Vy 74 knots Vx 62 C 12
• 74 12 86 suggested for cruise climb.
• P.O.H. shows 70 85Kts for cruise climb
• A more efficient climb. Better engine cooling
  with a lower, better deck angle. Source, Fly
• the Engine, Kas Thomas

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Flt. Planning - Figuring ISA

• Intl Standard AtmosphereISA
• Found in the P.O.H. in performance charts
• ISA is 59F or 15C at sea level, 29.92hg
• To find ISA at altitude take cruise altitude, x
  2, subtract 15, then change the sign (/-)
• 5,000 5 x 2 10 - 15 -5 becomes 5.
• 10,000 10 x 2 20 15 5 becomes -5

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Figuring TAS

• How to find your approximate TAS
• TAS increases approximately 2 per 1000
• What is your indicated altitude?
• Double the 1st digit, and add to the IAS.
• Result should approximate TAS
• Example 3000, and 120 knots, TAS is 3 x 2
  6, 120 6 126 knots

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The ice tea airspeed formula

• Airspeed relationships how to remember
• The iceT formula indicated calibrated,
  equivalent (applies to jets), True Airspeed. TAS
  increases with altitude. Indicated will decrease
  with altitude due to less dynamic pressure in the
  Pitot tube

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Rule of 60

• At cruise TAS, each degree of crab angle
• x TAS multiple (601, 1202, etc)
• crosswind component
• Ie., _at_ 120 knots, each degree of crab is
  caused by a 2 degree x-wind component resulting
  in a x degree drift correction.
• Ex., 5 degrees left x 2 10 knot cross
  wind

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Maneuvering Speed Va

• Maneuvering Speed Va 1.7 x Vs1
• Reduce Va by 10 for each 20 reduction in gross
  weight. Or, reduce by 1 for each 2 reduction in
  G.W.
• Remember, you are always BELOW G.W. at cruise.
  You burned fuel on taxi, takeoff and climb.
• All V speeds are predicated on G.W., so adjust
  accordingly for best performance.

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Engine failure A, B, Cs

• Airspeed best glide
• Best place to land straight ahead, to the side,
  or behind you?
• Aircraft Control maintain control!
• Know your emergency checklist!

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Engine Failure, Maximum Glide

• Weight has no effect on max glide range
• Weight does have an effect on glide speed
• Reduce glide speed 5 for each 10 reduction in
  gross weight
• With a headwind, increase glide speed by 50 of
  the headwind component. Glider
• pilots use this technique.

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Converting KTS to MPH

• Add 15, or multiply by 1.15
• 100kts 115mph

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Icing

• No aircraft is certified for CONTINUOUS flight in
  KNOWN icing conditions
• Icing/deice certification is only for flight
  THROUGH icing. Ref. FAR 25 Appendix C, icing
  certification
• Check your P.O.H.
• From, Professional Pilot, 3rd. ed., John Lowery

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Weather

• A rough rule of thumb for avoiding/escaping icing
  conditions but it varies each time
• Climb in a cold front towards colder temps (away
  from ice) if temps in the bases of developing
  cumulus clouds is -12C or warmerexpect heavy
  icing
• Descend in a warm front to warmer temps below
• Sources, Severe Weather Flying, Dennis Newton
• Weather Flying, Bob Buck

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Weather/TRW rules

• Storms tend to be stronger when the cold frontal
  passage occurs in the afternoon or evening. This
  is because the air can get more unstable out
  ahead of the front (i.e. daytime heating).

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IFR Standard Rate Turn bank angle

• Take 10 of the IAS and add 5.

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Ground Speed

• Rough estimate
• Add or subtract all of the headwind or tailwind
• Add or subtract ½ of a quartering head or tailwind

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Calculating Ground Speed - piston drivers

• Note the time to fly a distance ie., 30NM
• 30/15 15x 4 60 4 x 30 120
• 15 min to fly 30NM. G.S. 120kts.
• 10 min to fly 25NM 10x660 6x25 150 kts

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Ground Speed Check - VLJ drivers

• For faster aircraft (at least 250 kts.) there is
  another G.S. check
• Note the distance travelled in 36 seconds on the
  DME and multiply by 100.
• 36 seconds is 1 of an hour.
• So, if you travel 3NM, ground speed is 300 kts.

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How to plan descents

• Suggestion altitude to lose times 2 (500 FPM for
  pax comfort), times ground speed in miles per
  minute (1,2, 3, etc.), this is how many miles you
  will cover descendingadjust as needed for wind
  and plan when to start down accordingly

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Descent planning from the flight levels

• Multiply cruise altitude ( thousands of feet) x
  approx. 3 (depending on the aircraft and winds)
  to determine the approximate start of descent.
• To descend from FL 250 25 x 3 75
• Begin descent 75 NM out

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Intercept the glideslope

• At G.S. intercept, lower the nose exactly
  whatever the G/S angle is, as shown on the
  approach plate. Capture is automatic.
• This is typically 3 degrees.
• source, Barry Schiff, Proficient Pilot

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Flying the glideslope

• Determine the proper ILS descent rate
• Standard ILS descent rate 300/NM.
• Take IAS / 2, add a zero this is your Rate of
  Descent 100kts / 2 50, add a 0 500 FPM.
  120 kts 600 FPM
• Or, use this to figure the altitude to be at a
  given distance from a runwayfor a stabilized
• approach

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Landing

• Approx. 42 of G.A. accidents occur during
  approach and landing
• If the runway is wet and ungrooved, the landing
  ground roll doubles
• Crossing the runway threshold higher than 50
  feet landing distance increases 200 for every
  10 of excess height
• Every 10 kts of excess speed increases landing
  distance 20

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Misc

• For each 1000 above S.L., the takeoff run will
  increase 12

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Others

• Rollout from a turn lead your bank by ½ the bank
  angle
• Most structural icing occurs between 0C - 10C

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Your own

• Rules of Thumb???

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Thank you!

• j.mahany_at_charter.net
• www.johnmahany.com

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