Flying in weather
Preflight must include pre-heating the engine and oil, fingertip examination of flying surfaces, and free movement of controls is essential. Don't hand prop to start on a slippery surface. Deicing is best done inside a hangar. Some deicing fluids may adhere to the flying surfaces and act just as ice would in destroying lift. Some aircraft are powerful enough to takeoff with out tires rolling. Check tires for their ability to roll.

It is a practical understanding of weather that keeps aviators safe. Any trip of 750 miles is sure to encounter below VFR weather. Anytime the weather gives you doubtful feelings it is best to exercise the judgmental skill that cancels the flight. By knowing the weather you can know what you would do before the need to make a change in plans. Safety lies in knowing how to deal with the weather within the operating limitations of your aircraft. It is not a "failure" to cut your potential losses by turning back. On the other hand, you will fly in weather if the utility of flying is important.

Pilots and passengers die every year from exposure to the weather elements. Usually, death is a result of failure to anticipate the possible weather and dressing accordingly. Hypothermia is the culprit and it takes only wind, not cold to bring death. Wind plus being wet accelerates the onset and ultimate result.

The most dangerous weather is that of which you are unaware. The signs of adverse weather are always available if we look for them. Wind shear is never inadvertent. There is a ratio between safety and aircraft utility. This ratio varies with every flight. By taking the time to study the probabilities, keeping the final briefing inside the hour of departure, and (ideally) getting a look at the radar depiction you will not be surprised.

Begin your cross-country flight planning four or five days before the day of the flight. Continue your planning right up to the day of the flight. You make adjustments, including cancellation, based upon any information that will not fit into your model of what it takes to make a safe flight. In the Nino year past experience must be set aside and forecasts as well as plans will be flexible even to the last moment.

You are looking at the jet stream locations, frontal movements, and airflow around pressure centers. You are looking to atmospheric instability that will cause weather you do not want to encounter. You don't want rising air and condensation. A good pilot must apply what he has learned to what he sees happening. The good pilot will insist on at least one standard briefing before the flight. Inform the briefer of your total planned flight as well as any options you can think of. VFR you don't need an alternate but you should have an alternate plan anyway. Follow up with abbreviated briefings just before departure and stay in contact with Flight Watch. Accept VFR flight not recommended (VNR) and any mention of icing as sufficient reason to re-think making the flight at all.

Daylight Savings Time changes the way we fly. We do not fly as frequently so the accident frequency declines and the influence of weather on the occurrence of accidents increases. This is a time of more night when those accidents that do occur tend to be more serious. Accident rates at night tend to occur more often the less experience at night the pilot has. Night flying difficulty is directly related to what VFR pilots see outside and what IFR pilots see inside. Aircraft and ATC system failures are more critical at night. The transition from instrument to visual by the single IFR pilot is a killer.

There is no FAR that requires a pilot to make in-flight weather checks but thanks to Flight Watch this is easy to do from 6 a.m. to 10 p. m. local time any where in the United States. There is only one nationwide frequency of 122.0 that is available almost anywhere above 5000' AGL. For situations where 122.0 won't work consider the high-level frequencies of 135.7 or 134.52 frequencies usually reserved for high altitudes. The process of contacting Flight Watch only requires that you include the name of the closest VOR along with your identification. You will know you have a weather problem when you experience turbulence and cumulus clouds.

So called Judgment errors cause most aviation accidents. Terrain is a frequent corollary for judgment errors, actually nearly 30 percent. Another 70 percent are related to VFR weather into IFR weather, fuel complexities, exceeding aircraft capabilities and social pressures .

Weather Training
1996 weather related accidents was 68.2% with 58.9% being VFR into IMC. It is my opinion that proper exposure to weather conditions in familiar areas will enable a pilot to maintain situational awareness and make sensible avoidance decisions. To teach this requires that we fly into weather. Never fly into deteriorating weather and always fly into improving conditions.

Gradual exposure into the conditions along with the limitations of VOR navigation and radio communications is important. I feel that only exposure to these conditions in an instructional situation can overcome the emotional and intellectual paralysis that accompanies a virgin entry into such conditions. I have so exposed every student I have ever taught and have empirical evident that it is the way to go.

Every lesson is a weather lesson. We look at the windsock, the clouds, and the winds before getting the plane. After solo I deliberately plan a SVFR flight back and fourth between neighboring airports. Living on the West Coast makes finding this situation relatively easy. These are airports that we have flown to before but under better weather conditions.

It is only by actually experiencing such a flight can a pilot can fully understand just what is meant by remaining within 700' or 1200' AGL while remaining clear of clouds. Counting 5000' runways for each mile visibility can be difficult. It helps if you are so familiar with the airport checkpoints that you can give an exact building, bridge, intersection or common visual checkpoint when ATC asks for a position report. This kind of flying is not recommended in unfamiliar territory. The advent of El Nino has made for some strange weather but when traditional patterns return it becomes possible to make more realistic projections micro weather areas.

VFR Weather
Determined by visibility, cloud clearance, and ceiling
Standards for VFR below 10,000' and night:
Visibility of three miles
500 below, 1000 above, 2000 lateral of clouds
Ceilings 1000' AGL
(Night exception 1/2 mile of runway below 1200')
Class G Airspace Operations;(700/1200 AGL)
Visibility 1 mile daytime
Clear of clouds

Effects of Density Altitude
Heated molecules increase in speed and need for a greater space. The distance between them increases and the density decreases since for every unit of space there are fewer molecules. Lifting surfaces rely on the weight of passing air molecules to produce lift. Altitude density varies from sea level to space. A wing produces the most lift at sea level because of the density (closeness together) of the molecules. In space a wing does not produce lift since there are no molecules.

In the atmosphere, the air molecules near the surface of the earth are held closer together through molecular attraction and gravity than those molecules higher up in the atmosphere. The higher up you go in the atmosphere, the fewer the molecules. Density decreases as you go up in altitude.

Factors are altitude, temperature, humidity and low barometric pressure. Effects are wings lose lift, propellers lose efficiency, and nonturbo engines lose power. Results are that higher true airspeeds are necessary taking longer runs before reaching rotation speed. The climb will be more shallow even at higher true airspeeds.

A 2000' altitude above sea level will result in about 25% reduction in takeoff and climb performance. A sea level rotation of 70 knots ground speed will be 80 knots ground speed at 8000'. Even turbo performance only helps engine power without any effect on propeller efficiency or wing lift. You should double all book(POH) numbers because there are complicating factors such as the following.

True airspeed is only varied by about 5% by leaning. Speeds will be faster the cooler it is. This extra speed is reduced somewhat by the drag of denser air.

--The time of day that you fly makes a great difference.

--The lighter you fly the better your performance. you may be well advised to make two flights with half load instead of one flight that doesn't get you where you are going. A 20% reduction in load gives a 36% performance increase.

--Learn to manage the mixture. Lean for altitude, takeoff and climb. Without an EGT lean for peak rpm. You can lean at less that 75% power even for takeoff. With an EGT you can use the EGT setting of a cruise altitude as a takeoff reference setting. Except for full power rich mixtures are unnecessary. Keep the mixture leaned during descent to keep the engine warmer.

--The best way to learn flying at density altitude conditions is to fly with an experienced pilot several time into different conditions. This will relieve anxieties you probably have that only knowledge can overcome. Personally I flew across the Sierras three times with an instructor before attempting the flight by myself. I have never regretted the time, cost or experience in doing those flights.

--Headwinds require the use of more power to mitigate the percentage effect adverse winds have on ground speed. Fly faster into headwinds. The slower you go the more important it is to use fuel planning.

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