Search Ceiling (max search altitude): climb rate of 300 feet per minute

Effect of Weight on climb performance (less is better):
C-172: for each 100 lb. weight reduction, ROC increases 60 fpm
C-182/Arrow: for each 100 lb. weight reduction, ROC increases 80 fpm

Most V speeds change as 1/2 the percentage of the change in weight
(square root of the ratio of weights is more precise)

Bank angles for search:

Max of 30° while scanning

Max of 45° to position aircraft for a pass

60° reserved for emergency escape (may produce altitude loss)

Canyon turn: entry speed ~ 1.5 Vso, approach flaps, 60 degree bank,
pull to stall warning (AVOID ACTUAL STALL), may lose altitude.

Modified Wingover: Pull up to ~ 30° pitch, when airspeed drops to ~ 70 kts
apply rudder in direction of turn, ailerons neutral; after 90° of turn,
relax back pressure and rudder pressure.
Recover from nose-down with gentle back pressure.

1 knot ~= 100 feet per minute

Crosswind estimation: at 100 kts, each 6 degrees of crab
is equal to 10 knots of crosswind component

Direction/velocity estimation: Over a distinct point, enter a 45 degree turn
at 100 KTAS. After a full circle , check position back to the point.
wind direction is from the point to current position
velocity in knots is the distance in 1000's of feet times 2

Turn Radius (in feet):
45 degree bank, ~= (speed in kts, squared) ÷ 10 (11.26 for precise answer)
30 degree bank ~= 75 % larger
60 degree bank ~= 40 % smaller

At 100 knots, a 45 degree bank turn has a radius of ~900 feet
At 100 knots, you travel 1000 feet in 6 seconds.

Time in seconds to make a 360° turn at 45° bank ~= speed in kts ÷ 3
same rules for as for radius for 30° and 60° banks above apply for time

3° descent ~= 20/1 @100 kts, 3° = 100/20 = 5 kts or 500 fpm OR
multiply speed in knots by 5 to get fpm (100 kts x 5 = 500 fpm)
4.5° descent: multiply speed in knots by 8 to get fpm descent rate

Approach ridges at 45° angle when within 1/4 to 1/2 mile
Always remain in a position where you can turn toward lowering terrain
Safe to cross a ridge when you could cross the ridge in a power-off glide
Fly along windard/downwind sides of canyons to allow use of full width to turn around

Pressure Altitude: set altimeter to 29.92 to display, or
subtract 1000 feet per inch of mercury above 29.92 (add below 29.92)

Standard Temp: 59°F - 3.6° per thousand feet MSL (Standard Lapse Rate)

Density Altitude: Pressure Alt + 66 x (Ambient Temp - Std Temp °F) or
add 600 feet for each 10 °F above Std Temp

Temp Conversion: Double °C and add 30 for °F (exact °F = °C x 9/5 + 32)

True airspeed increases ~ 2% per thousand feet of altitude

For each 10 knots wind speed, fly 1000 feet above terrain

If wind is > 30 knots at peaks, don't go unless absolutely necessary

Mountain Wave conditions (AVOID):

1) forecast winds aloft at alt of peaks > 30 kts
2) wind direction +/- 30 degrees of perpendicular to obstruction
3) wind velocity steadily increasing with increasing altitude
(wind velocity at 34,000 feet > 75kt is a strong indicator for wave)
4) wind direction relatively constant with increasing altitude

Wave Downdraft Escape:

If descending at Vy faster than you should be ascending,
1) turn toward lower terrain,
2) increase speed to cruise speed, (use Va if any turbulence is present)
to fly out of the downdraft area

Turning downwind is the fastest direction to fly out of the downdraft

If you don't have 70% of takeoff speed at midpoint of runway, abort takeoff
as you won't reach takeoff speed before the end of the runway.

Takeoff distance varies as the square of the weight

For each 1000' DA above sea level, add 12% to sea level takeoff distance,
add 4% to landing distance.

Takeoff surface: firm turf: add 7%
rough, rocky, or short grass (< 4" high): add 10%
long grass (> 4" high): add 20-30%
soft field: add 23-75%
mud or snow: add 50+%

For each 1% of downslope, subtract 5% from takeoff distance
For each 1% of upslope, add 7% to takeoff distance

O2: required for pilot after 30 minutes above 12,500 feet
at all times above 14,000
for all passengers above 15,000
Recommended for search operations above 10,000

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