Transcript Avitation Rules of Thumb - Society of Aviation and Flight

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Aviation Rules of Thumb
John Mahany, ATP/MCFI
Flight Advisor, EAA Chapter 7
FAASTeam Lead Rep, KLGB
September 13, 2011
ATA SmartBrief, 8/30/11
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Automation prompts safety officials' concern about
pilots' skills
Airplanes 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, cochairman 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.
ATA SmartBrief, cont.
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"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."
More on piloting skills
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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."
Some Aviation Rules of Thumb
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Navigation reciprocals
Normally aspirated & Turbo-charged
Density Altitude
Takeoff Performance
Crosswind Component
Vx & Vy
Cruise Climb
More Aviation Rules of Thumb
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Flight Planning & ISA
Figuring TAS
Figuring Va
Engine Failure
Converting KTS to MPH
Maximum Glide
Icing, weather, descent planning…
Your own?
Navigation reciprocals
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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?
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Lexington, KY CRJ takeoff accident,
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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….
Comair 5191 CVR
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Pilot: Thrust Set
Pilot: That is weird, No Lights
Pilot: Yeah
Pilot: 100 Knots
Pilot: Check
Pilot: vee one
Pilot: Rotate
Pilot: Whoa!
Generic Takeoff Briefing
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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 ??
Normally aspirated engines
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A normally aspirated engine – only produces
rated Hp at Sea Level on a ‘Standard Day’, or
ISA; 15C or 59F
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It loses 3 ½ % - 4% hp for each 1000’ increase
in altitude.
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Every 10 deg. F/6C above ISA results in 1% less
power output
Turbo-Charged Engines
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Takeoff fuel flow –
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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 < 380F
– Source, Mike Busch, Savvy Aviator
Density Altitude
For every 10F above ISA, add 600’ to
the airport elevation to figure density
altitude and your airplanes performance.
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source, Richard L. Collins
Density Altitude
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From AOPA Safety Advisor #6,
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Mastering Takeoffs and Landings
‘the simple act of taking off or landing
accounts for 50% of all general aviation
related accidents’
Big Bear City, CA, takeoff 6748’ msl
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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
Takeoff performance
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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
Takeoff flap setting
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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.
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source, Mountain Flying Bible
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! 
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source, Mountain Flying Bible
Crosswind component
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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
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A more efficient climb. Better engine cooling
with a lower, better deck angle. Source, Fly
the Engine, Kas Thomas
Flt. Planning - Figuring ISA
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Int’l Standard Atmosphere…ISA
Found in the P.O.H. in performance charts
– ISA is 59F or 15C at sea level, 29.92”hg
– 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
Figuring TAS
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How to find your approximate TAS
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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
The ‘ice tea’ airspeed formula
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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
Rule of 60
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At cruise TAS, each degree of crab angle
x TAS multiple (60=1, 120=2, etc)
= crosswind component
Ie., @ 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
Maneuvering Speed Va
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Maneuvering Speed; Va = ~ 1.7 x Vs1
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Reduce Va by 10% for each 20% reduction in gross
weight. Or, reduce by 1% for each 2% reduction in G.W.
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Remember, you are always BELOW G.W. at cruise. You
burned fuel on taxi, takeoff and climb.
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All ‘V’ speeds are predicated on G.W., so adjust
accordingly for best performance.
Engine failure A, B, C’s
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Airspeed – best glide
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Best place to land – straight ahead, to the
side, or behind you?
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Aircraft Control – maintain control!
– Know your emergency checklist!
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
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Add 15%, or multiply by 1.15
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100kts = 115mph
Icing
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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
Weather…
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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 warmer…expect heavy
icing
– Descend in a warm front to warmer temps below
– Sources, Severe Weather Flying, Dennis Newton
– Weather Flying, Bob Buck
Weather/TRW rules…
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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).
IFR Standard Rate Turn bank
angle
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Take 10% of the IAS and add 5.
Ground Speed
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Rough estimate
– Add or subtract all of the headwind or
tailwind
– Add or subtract ½ of a quartering head or
tailwind
Calculating Ground Speed piston drivers
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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; 10x6=60; 6x25 = 150 kts
Ground Speed Check VLJ drivers
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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.
How to plan descents
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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
descending…adjust as needed for wind
and plan when to start down accordingly
Descent planning from the
flight levels
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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
Intercept the glideslope
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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
Flying the glideslope
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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 runway…for a stabilized
approach
Landing…
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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%
Misc…
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For each 1000’ above S.L., the takeoff run
will increase ~ 12%
Others…
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Rollout from a turn; lead your bank by ½
the bank angle
Most structural icing occurs between 0C 10C
Your own
Rules of Thumb???
Thank you!
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[email protected]
www.johnmahany.com
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