633Pneumatic Deice Boots Turboprop Aircraft

The following discussion is based on comments by Eugene G. Hill the FAA's chief scientific advisor for environmental icing. Eugene Hill had 36 years experience with Boeing, including extensive work on icing certification. He had a significant role in developing the FAA's current icing strategy. Manufacturers of most turboprops and some small jets are reviewing their recommended de-ice boot operating procedures and, in some cases, rewriting them. The activity stems from the FAA's July 1999...

727 InFlight Training Aircraft

Per-flight briefing similar to that for the simulator program. Operation of de-ice systems. Stall recovery at the buffet, aggressive use of attitude and power. Unusual attitude recovery, ADI EADI presentation and interpretation, recovery technique. A key feature of unusual attitude recoveries is the ability to interpret the ADI EADI. Familiarisation with these presentations does not necessarily involve elaborate simulation rather it may be accomplished using simple models made from cardboard or...

177Ice Intensity Pilot Action

Rate of accumulation of ice is slightly greater than the rate of loss due to sublimation. (b) Light The rate of accumulation may create a problem for flight in this environment for one hour. Unless encountered for one hour or more, de-icing anti-icing equipment and or heading or altitude change not required. (c) Moderate The rate of accumulation is such that even short encounters become potentially hazardous. De-icing anti-icing required to remove prevent...

24 Prevention Recognition and Remedial Practices 241 Prevention

Whilst the following provides a general guide to assist pilots to avoid induction system icing, the Pilot's Operating Handbook or Flight Manual must be consulted for specific procedures applicable to a particular airframe and engine combination. The procedures are likely to vary between different models of the same aircraft type (a) heating the intake air in an exhaust heat exchanger before it reaches the carburettor prevents carburettor icing, (Design Requirements typically demand a...

54 New Zealand Statistics

During the five years from January 1995, New Zealand CAA recorded 487 aircraft accidents and 1940 incidents, a total of 2427 occurrences. 13 of these were attributable to in-flight icing - a rate of .53 . This analysis has been treated with caution due to the absence of a dedicated icing database and reluctance of some pilots to report icing occurrences. Nevertheless the rate is significantly lower than the FAA, so low in fact that Authority research led to the conclusion that a warmer...

255Immediately before Take off

Induction icing can occur when taxiing at low power or when the engine is idling. If the weather conditions appear to be conducive to the formation of induction icing then the HOT position should be selected before take-off for sufficiently long enough to remove any accumulation which may have occurred. If the aircraft is kept at the holding point in conditions of high humidity it may be necessary to run up the engine to the take-off power setting more than once to dear any ice which may have...

724An Alternative Program

Alternatively, training should focus on classroom education supplemented with practical training in either a simulator or an aircraft, the goal of the training being enhanced pilots knowledge and awareness. This awareness should include icing considerations, recognition of icing situations, escape strategy, recognition of potential upset situations and escape from these situations. This training needs to be formally incorporated during every phase of an operator's pilot training program...

21Introduction

Piston engine induction system icing, commonly, but not completely accurately, referred to as 'carburettor icing' may occur even on warm days, particularly if they are humid, IT CAN BE SO SEVERE THAT, UNLESS CORRECT ACTION IS TAKEN, THE ENGINE MAY STOP. Induction system icing is more likely at low power setting such as those used during descent, holding, on the approach to a landing or during auto-rotation on a helicopter. Statistics continue to show an average of 10 occurrences, including 7...

162 Ice Secretion

The shape of the ice that forms and the amount of ice that accumulates primarily influence aerodynamic performance degradation while the amount of liquid water in the cloud and the duration of the exposure to icing primarily determine the quantity of ice collected. Cloud droplet size is generally a secondary consideration. Temperature can determine the amount of accretion if it is close to freezing, some of the intercepted water droplets blow off before they can freeze. Ice accretion shape is a...

153 Wing Tip Stalling

Normally, washout helps to ensure that the symmetric stall starts inboard, and spreads progressively, so that roll control is not lost. Greater ice accretion has probably occurred at the tip, leaving it more impaired aerodynamically than the inboard wing section. Stall, instead of starting inboard, may start at the tip. Because the tip section may have a sharper nose radius and probably has a shorter chord, it is a more efficient ice collector. As a result, ice accretion at the wing tip may be...

884 Program for Relief of Ice Drag Fuel Penalty in Critical Fuel Scenario

This program for ice drag fuel relief applies to the mid-Pacific routes between the U.S. mainland and Hawaii. This area is relatively free of icing. Data from the U.S. Marine Climatic Atlas indicates percentage frequency of icing in winter ranges from a high of 30 in Seattle, to 12 in Oakland, to 0 in Hawaii. The program has certain constraints. There is no relief granted in this program for the anti-ice penalty (use of) which is provided in the manufacturer's data (e.g., 6 fuel penalty for use...

22Induction System Icing

There are three main types of induction system icing The most common type of induction system icing is carburettor icing which is caused by the sudden temperature drop due to fuel vaporisation and reduction in pressure at the carburettor venturi. The temperature reduction may be as much as 20 - 30 C and results in moisture in the induction air forming ice. The ice gradually builds up, constricting the venturi and, by upsetting the fuel air ratio, causes a progressive decrease in engine power....