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By The Book

Preflight action

One of the fundamental regulations under which we operate aircraft is also one of the most comprehensive. Federal Aviation Regulation 91.103, "Preflight Action," requires that "each pilot in command shall, before beginning a flight, become familiar with all available information concerning that flight."

"All" is a scary word. A massive information dissemination system exists to provide data to pilots, but to become familiar with all available information for a particular flight requires no small commitment of effort by the pilot. FAR 91.103 tells us basic information we must include in our preflight planning for any flight: "runway lengths at airports of intended use and...takeoff and landing distance information...relating to aircraft performance under expected values of airport elevation and runway slope, aircraft gross weight, and wind and temperature."

This specificity has good reason. According to figures compiled for the 1991 edition of the AOPA Air Safety Foundation's General Aviation Accident Analysis Book, takeoff and landing accidents accounted for more than half of the nearly 9,000 accidents between 1982 and 1988 in which pilot action or inaction was the major causal factor. The study's authors concluded that "pilot knowledge or understanding of necessary procedures for operation in various wind conditions (gusts/crosswind), varying field conditions, runway lengths, and elevation and temperature effects were apparently lacking in many of the accidents."

But "knowledge or understanding of necessary procedures" is unhelpful if the pilot is unaware of adverse factors due to inadequate preflight preparation.

At least four information sources must be consulted to satisfy this part of the regulation.

The primary reference for airport information is the National Ocean Service's Airport/Facility Directory. Regardless of whatever flight-bag planning aids you carry, the A/FD should be considered essential. Not only is it updated regularly (every eight weeks), it carries a government seal of approval right on the cover: "Published in accordance with specifications and agreements approved by the Federal Aviation Administration and the Department of Commerce." This is not to say that no other information source is similarly blessed, but some carry a disclaimer such as "does not comply with regulations governing publications." If you want to go by the book, the A/FD is one book to go by.

The primary reference for aircraft performance is the pilot's operating handbook or airplane (or rotorcraft) flight manual. If your airplane dates from the bad old days before POH standardization, extracting the needed information may be difficult or impossible. In a few cases, enterprising individuals have gone back to original certification data and compiled a modern (though not necessarily manufacturer- or FAA "approved") POH. An outstanding example is Douglas Killough, who, with the assistance of the International Comanche Society, compiled "aircraft information manuals" for 10 models of Piper Comanche and four models of Twin Comanche. Type-specific clubs or associations are a valuable resource for finding such aftermarket publications (a list of such groups begins on p. 29 of the 1992 edition of AOPA's Aviation USA). If no official or quasi-official information is available, buy a copy of The Axioms of Flight, by James Embree ($19.95 postpaid from Flight Information Publications, Post Office Box 16616, St. Louis, Missouri 63105; telephone 314/469-1488). This excellent compilation of rules of thumb, formulas, graphs, tables, and other information should be in every pilot's library anyway.

Our third prerequisite is weather information to provide the wind and temperature variables to determine our runway requirements. If the airport reports weather, the information will be available through a flight service station briefing or the Direct User Access Terminal (DUAT) system. If the airport does not report weather, many FBOs can provide wind and temperature information. If no FBO is on the field, examine reports from nearby airports. Another alternative is NOAA Weather Radio, which transmits on frequencies at 0.025-MHz intervals between 162.400 and 162.550 MHz within reception range of about 90 percent of the U.S. population. Also check the A/FD to determine if the airport is equipped with an automated weather observing system (AWOS); it will be listed under "Weather Data Sources" immediately following the "Airport Remarks" entry. AWOS units are normally connected to a telephone line for remote access, and the number is in the A/FD.

One other source should be consulted during our preflight preparation — notices to airmen. Notams contain time-critical information that is either temporary or not known sufficiently in advance to allow publication on charts, in the A/FD, or in other flight information publications. Because notams report airport and runway closures, they should be examined before even a local flight. More on notams in a moment.

FAR 91.103 also tells us that for a flight under IFR or not in the vicinity of an airport, we must familiarize ourselves with "weather reports and forecasts, fuel requirements, [and] alternatives available if the planned flight cannot be completed....

Initiating or continuing VFR flight into instrument meteorological conditions, by both instrument-rated and non-instrument-rated pilots, is a persistent accident cause. Weather was a factor in one out of 10 pilot-related accidents in the AOPA ASF study cited above. But weather was a factor in one in five accidents in twin-engine and retractable-gear single-engine airplanes. The study noted that "a large number of weather-related accidents implicated a lack of weather briefing prior to flight, or receipt of an incomplete briefing due to pilot impatience, or pilot failure to understand the briefing....

Fuel mismanagement — either through fuel exhaustion, starvation, or contamination — accounted for 10.3 percent of the total 16,220 accidents in the ASF study, and 55.5 percent of the fuel-related accidents were due to fuel exhaustion. Among others, the study cited factors such as "initiating the flight on partially filled tanks...attempting to fly beyond aircraft endurance limits, poor flight planning with regard to fuel management, unexpected headwind encounters and failure to divert, and failure to refuel during interim stops."

Wind and forecast weather conditions must be taken into account in determining fuel requirements. For VFR flights, we must have enough fuel to fly to our intended destination and then continue, at normal cruising speed, for 30 minutes in daytime or 45 minutes at night (20 minutes day or night in a rotorcraft) (FAR 91.151). For IFR flights, we must be able to fly to our destination, divert to our alternate airport (if one is required), and then continue, at normal cruising speed, for 45 minutes (30 minutes in a rotor-craft) (FAR 91.167).

Some pilots confuse 91.103's admonition regarding "alternatives" with 91.167 and 169's rules regarding selection of an "alternate" airport for IFR flights under certain forecast and/or reported weather conditions. But 91.103 is much broader in scope. It asks us to resolve, before we take off, a course of action to follow if the flight cannot be completed as planned. One examiner we know asks instrument rating candidates what they would do if they lost all communication and navigation capability while enroute with no VFR weather within the range of the airplane. What she wants to hear is that they would not initiate a flight in such weather conditions because the "alternatives available" are exceedingly poor. (Before you pooh-pooh her scenario, let me add that I was a passenger on a flight that suffered that exact misfortune. We also lost our gyroscopic flight instruments. Over the mountains. We were lucky. It wasn't at night.)

It should go without saying that current aeronautical charts are necessary for adequate preflight planning. Sectionals are issued every six months, IFR enroute charts every eight weeks, and instrument approach procedures every eight weeks with an update "change notice" four weeks into the cycle. Again, the notam system is essential to bring to pilots' attention the latest data that become available between publication cycles. In addition to airport information, for example, notams contain changes in the status of navigational aids, ILSs, radar service availability, and other information es- sential to planned enroute, terminal, and landing operations.

The usual way of receiving notams is during a weather briefing by an FSS specialist. However, you will only be provided with notams if you get a standard briefing; if you request an abbreviated briefing or an outlook briefing, you must specifically request notams. Published notams — also called printed notams, issued every two weeks — are also not provided unless specifically requested. If your destination airport is not within the FSS's local area, or if your flight will take you more than about 400 miles from the FSS's location, you will have to call the appropriate FSS(s) for complete notam information. Pilots have access to limited notam information through DUAT, but complete notam information requires a call to an FSS.

One more piece of information required by 91.103 is "any known traffic delays of which the pilot in command has been advised by ATC. "This information, according to the Airman's Information Manual, will normally be provided during a standard FSS briefing. If special air traffic rules or requirements are in effect, they are usually published in the "Notices" section of the A/FD, following the airport/facility listings, as are data for operating at high density traffic airports (HDTAs). They may also be published in notam form: Arrival and departure procedures for the Oshkosh and Sun 'n Fun fly-ins are examples.

Another important part of preflight planning is preparing and filing a flight plan. For VFR flights, this is a cheap insurance policy. For IFR flights, or VFR flights into a coastal or domestic air defense identification zone, it is required.

For a pilot to become familiar with all available information for an upcoming flight, he must be prepared to expend some time and energy. The A/FD, the notam system, other flight information publications, flight plans, FARs, and the operational information contained in the AIM are all significant parts of the process. Some pilots do not avail themselves of all the resources at their disposal. But the letter, as well as the spirit, of the law requires that we do the job right.

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