Ch. 14 - Extreme Weather Operations (Cold Weather Ops Only)

Question 1

If hangar space is available

Answer 1

the aircraft should be kept in a heated hangar when the OAT is forecast to be below 0c (32f)

Question 2

Exterior inspection

Answer 2

1. Fuel drains for ice (indicates water in tanks)
2. Inlets (specifically low points by swirl veins)
3. main and tail rotor blades as well as flight controls.
4. Vent ports

Notes:
1. Never scrape or chip ice
2. Failure to remove will cause engine damage
3. Can cause serious aerodynamic / structural effects in flight.
4. Can cause false and erratic indication

Question 3

Interior inspection

Answer 3

1. Check PCLs for freedom of movement before engine start. (frozen spindles)
2. Flight controls can be difficult to move. if the controls are not sufficiently free for a start up and low power warm up - heat the controls

Question 4

Engine Oil Characteristics

1. Oil pressure may

Answer 4

Remain at zero for 20-30 seconds after initiating the start.

Abor the start if there is no oil Px within one minute of initiating the start.

Question 5

Engine Oil Characteristics

2. Once oil pressure begins to indicate

Answer 5

It will increase rapidly and exceed the prescribed 100 psi limit…
… Px will decrease as temp rises…
… this condition is considered normal and should correct within 5 minutes..

Do not advance PCL to FLY before Px is indicating normal.

Question 6

Engine Oil Characteristics

3. The OIL FILTER BYPASS caution

Answer 6

may appear during cold weather starts….
… impending bypass has a thermal lockout below 38c to prevent PDI from popping…
… when engine oil reaches 38c the caution should disappear

Question 7

Engine Starting

Answer 7

Watch for rise in TGT within 40s.

If no rise is evident, prime the engine and attempt another start.

If there is no fuel overboard during the prime, inspect for ice the sumps and filters

Question 8

When on an icy surface

Answer 8

use the No-Rotor Start Procedure to prevent possible aircraft rotation.

Question 9

Equipment

LCD (Liquid Crystal Display)

Answer 9

Less brightness and slow to respond

0c or colder should turn on within 15 s

up to 15 minutes may be required before full performance is available

Question 10

Equipment

TA

Answer 10

TA battery charge will vary as a function of battery condition/ age

5c and below.. up to 45 min may be required before successful unfold or active transmissions.

Question 11

Snow Precautions

Answer 11

Running takeoffs are permitted if ground speed is held below 60KGS on level terrain before leaving the ground.

running landings are recommended on loose snow… clear of clouds under 15 KGS at touchdown

Question 12

Take off

Answer 12

A slight Yaw induced by the pedals can break the tires free

Question 13

Cruise

Answer 13

Fly on inst. over large unbroken expanses of snow.

Question 14

With ECS HOT

Answer 14

1. Max torq. available is reduced by up to 5% per engine
2. Fuel flow is increased by 45 lbs per hour PER ENGINE

Question 15

With Engine Anti-ice on

Answer 15

Maximum torq. available is reduced by up to 18% PER ENGINE and..

… can be reduced up to 49% if the inlet anti-ice valve has malfunctioned.

Question 16

Icing conditions

Answer 16

5c and visible moisture…

… inlet guide veins and and inlet are susceptible to icing

anti-ice SHALL be turned on

Question 17

Ice Damage to the T700 Engine may be charactorised by

Answer 17

high pitched noise with no associated power loss or secondary indications

Question 18

Helicopters equipped with blade De-ice

Answer 18

Flight is permitted into known or forecasted trace or light icing conditions.

Question 19

Ice Rate Detector

Answer 19

Mounted on the No. 2 eng. cowling..

.. senses accum. of ice and activates ICE DETECTED caution…

… turns on a heater to melt ice, making the ICE DETECTED caution disappear

… the rate at which this sequence repeats itself indicates icing severity level.