User manual

Section Appendix A.4 Part B
We taxi on the step with the floats up but there are risks in raising the floats before the
aircraft is safely airborne. Although raising the floats does reduce drag and marginally
improve acceleration, digging in a half raised float will be more damaging to the float
support structure and will increase the likelihood of a waterloop or cartwheel.
Once at climb speed and Climb power complete the after takeoff checklist.
11 TAKEOFF TECHNIQUE (GLASSY WATER)
In glassy water it is sometimes difficult to get the aircraft established on the step The
aircraft instead plows through the water and a considerable distance may be required
before hydroplaning is achieved. Some seaplane pilots rock the controls vigorously fore
and aft inducing a porpoising motion until the aircraft gets over the hump and onto the
step. There is no evidence that this aids the takeoff in Catalina flying boats. Once on the
step, nose attitude must be that best acceleration and this should be held until the aircraft
lifts off. Once in the air refrain from flying level in ground effect, just proceed in a climb
attitude and accelerate toward 95 kts. Only in this situation the engine failure after Take off
is considered less demanding then flying in ground effect over glassy water.
The takeoff path should be aligned to keep a shoreline or series of reference points in the
pilots view at all times. This is particularly important if the takeoff has to be abandoned
after leaving the water since otherwise the pilot has no idea where the surface is.
Depth perception on and after leaving the water surface is unreliable. It is critical that the
correct takeoff attitude be maintained until well after the aircraft leaves the water. Note the
attitude at takeoff, hold it with reference to the horizon an do not change the attitude until
high enough for depth perception to return, This is one take off where acceleration to 95
knots is less important than attitude stability.
If the takeoff must be aborted after leaving the water, achieve and maintain the correct
landing attitude until the aircraft touches. Remember, glassy water is harder than it looks.
Rough water is waves with air spaces between and the air at least is compressible. Glassy
water looks smooth but is very solid and can tear the nose doors off easily if attitude is
neglected.
12 TAKEOFF TECHNIQUE (CHOPPY WATER)
Where there are no large waves or swells but the wind is 10-15 knots there will be small
whitecaps and wave height of 1-2 feet. This is probably the roughest conditions that we will
operate in.
Takeoff in these conditions is similar to that discussed for light conditions but there will be
more spray during the early part of the takeoff run and holding the correct attitude for best
acceleration is difficult because of the waves.
Continuous small adjustments to the elevator input are required to maintain a constant
attitude, allowing the aircraft to accelerate to flying speed. Do not allow the aircraft to be
thrown into the air by the waves. Keep the correct attitude and let speed build, then ease
back on the controls at 55-60 knots and deliberately take the aircraft off the water and
continue with a normal Take-off technique.
13 TAKEOFF TECHNIQUE (ROUGH WATER)
There is no set point of transition from choppy to rough conditions. Rough water usually
implies strong winds which mean the aircraft will lift off at a lower ground speed,
shortening the time she is in contact with the waves. Countering that is the difficulty the
Rev No: 02 Stichting Catalina PH-PBY
Page: 6 01 April, 2006