Long and Short of It

Long trips are fundamentally different than short ones, but proper planning can even out the risk

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At the end of July every summer, thousands of pilots hear the sirens song luring them to Oshkosh. For many, the trip involves a long flight in a sport plane seldom flown cross-country. For a few, the challenge is too much.

Pilots who ignore the pilgrimage to aviations Mecca are not immune. Family vacations and the desire to explore tap into the quality that airplanes do best: long trips.

Long trips have many advantages over short ones. You can climb higher, get above the thermals and into cooler, smoother air. The airplane consumes less fuel in the thinner air and goes faster. You may be able to catch a favorable tailwind and whisk along over the countryside watching the GPS or DME count down.

While long trips offer these distinct advantages, they can be quite different from short cross-country trips. You will be venturing into a new part of the country where weather patterns will be unfamiliar, the availability of airports may be radically different, and you may eat farther into your fuel reserves than you have in the past.

Your thinking has to shift gears when planning for a long trip. Preflight planning for a relatively short trip can be fairly cursory and usually you can get away with that, but on a longer trip, the planning must be more detailed and thorough. Here are some pitfalls that may be waiting to snag you.

Traffic Delays
If you fly out of a very busy airport on a regular basis, then you are aware that sometimes there can be a long line of traffic waiting to take off and land. If you dont normally travel to busy airports, you may be surprised by the traffic congestion that can happen at and around a busy airport.

There are several reasons airplane traffic can stack up at an airport. Sometimes youll know about it in advance; sometimes you wont.

Delays can be caused by too many aircraft trying to operate at the airport – a problem that is exacerbated when a large proportion of the traffic involves flight training. Flight training involves slower aircraft and student pilots can tie up the radio. Where flight schools cater to foreign students, language barriers result in even slower communications.

Another big reason for delays at an airport is a weekend event, such as a fly-in or a special event in the same city. The Indy 500 and the Kentucky Derby, for example, can clog traffic for miles, but even college towns can be inundated when the football team has a home game. During such events, youll encounter aircraft of all varieties descending upon the local airports for a day or two before and after the big event. Plan on significant traffic delays.

The third big reason for traffic delays can be air carrier pushes or banks. Airline hub and spoke systems mean the air carrier brings a large number of aircraft into an airport during a certain time, then these flights depart about an hour later, creating very long waits on the taxiway.

Traffic delays can also result from a mechanical malfunction in an aircraft or airfield equipment. An airplane with a landing gear problem will receive priority handling, and that may necessitate closing down the airfield until the airplane is on the ground – and clear of the runway. In the meantime, you might be boring circles outside of the traffic pattern. The delays can be substantial if the aircraft lands gear-up because removal from a runway can be a very time-consuming process.

Of course, another big reason for traffic delays is poor weather. Weather forecasts for the destination can give you a clue about the potential for delays. If there is incoming weather such as low IFR, thunderstorms or fog, then count on traffic delays, even if flight service doesnt mention it during your weather briefing. The flow of airplanes into an airport substantially decreases when the weather goes from VFR to IFR.

If you are flying a trip VFR and arent using flight following, you may be completely surprised by traffic delays at your destination. I fell into this trap once when flying VFR from the Northern Rockies to Santa Fe, N.M. When I obtained my preflight weather briefing, flight service said nothing about delays because none were reported.

Unfortunately, while I was flying en route a pilot landed gear up and closed down the main runway at the destination. The weather was typical for the Rocky Mountains in the late springtime – severe clear and a million – so we didnt talk to FSS for a weather update. When I tuned into the airport for landing information, the radio was so jammed that I thought I was listening to New York Rapcon on a Friday afternoon. Since I had planned the flight with just over 30 minutes of fuel reserve, I could not really afford to hold outside the traffic pattern while waiting for the runway to be cleared. Luckily there were a couple other airports nearby where I could divert for fuel.

If you fly the trip on an IFR flight plan, you will be in constant radio contact with ATC and they will give you a heads-up about any delays.

Here are some hints that should clue you into problems at the destination. If ATC asks other traffic for their indicated airspeed and then asks them to slow down, it means traffic could be stacking up nearby. The computer algorithms in the FAAs traffic management software prefer to slow airplanes down en route rather than stack them in holding patterns.

As soon as you start hearing holding instructions for others, you should mentally shift gears and plan for the possibility of delays. You should also pull out your pen and be ready to copy down the holding clearance they have planned for you.

The effect of a traffic delay can be insidious, but it directly cuts into your time available for diverting.

If you get a delay early in a trip, you should assume that Murphys Law is alive and well on this trip and just plan for even worse delays yet to come. If ATC gives you vectors that take you away from your destination rather than toward it, that is as much a delay as a holding pattern.

Can you predict ATC delays? To some extent, yes, though many delays are unpredictable.

If you are traveling into a busy airport, count on it. If youre traveling on a Monday morning or Friday afternoon, plan on it. If the airport serves air carriers, you can get their reservation timetables and look for the pushes when most of their jets approach or depart the airport. If you are traveling to a location hosting a large event, such as the Super Bowl, check for Notams that may prescribe certain arrival procedures and plan on extensive delays due to ATC congestion.

A few months ago I flew into Indianapolis the day before the Indy 500. Our dispatchers had planned for ATC delays and we carried some extra fuel, but the biggest delay was one no one predicted.

A Marine Corps airshow over the race track conflicted with arrivals on the ILS. To make matters worse, the tower controller had to constantly give directions to the Marine aircraft. While we were being vectored for the ILS, I counted over 42 separate times that the tower controller had to provide instructions to the Marine aircraft.

That really backed up the arriving traffic and jammed up the radios. Sometimes you never know what will cause delays.

Weather
Long range flights also require your weather decisions to be made with a longer-term perspective. When you obtain your weather briefing, the weather forecast be can more than six hours old. As you near your destination on a four-hour leg, the forecast can be woefully out of date.

On a long trip, your chances of flying through a front are much greater. The mere fact that youll be in the air longer means you will encounter more weather and thus need to make better in-flight weather decisions.

Monitoring Flight Watch is a good idea. Youll hear many pilots report their flight conditions and Flight Watch will pass along the latest weather information. If you are a long distance from a repeater station, then youll have to contact flight service over nearby VORs. The transmit and receive frequencies are on the charts.

You must ensure that your aircrafts equipment and your skills can match the challenge of the weather. For instance, if you are flying near where embedded thunderstorms are possible, then weather radar and/or lightning detection are vital. If you are flying into low IFR, your aircraft instruments and your instrument proficiency needs to be acceptable.

Beware of differences in the way weather works if youre flying to a different part of the country. Out west, for example, the drier air produces thunderstorms with bases of 10,000 to 15,000 feet and excellent visibility all around. Its usually easy to see these single cells in the daylight and to fly around them.

In the humid air of the South, thunderstorms have much lower ceilings and tend to clump together more. These are much harder to avoid. Watch out for lowering ceilings. Those thunderstorms are much prettier to observe from the ground than from the air.

In the summertime haze of the South, its very difficult to distinguish between a cloud layer and just plain haze, so its easy to fly VFR into IMC. In fact, controllers in Alabama, Mississippi and Georgia routinely ask your conditions of flight.

Its also easy to find yourself flying under a cumulonimbus that is about to start developing heavy rain and lightning. You should plan your flight route so that an airport is always nearby for a quick divert.

If the weather drops at your destination, you ought to seriously consider diverting to an airport with better weather conditions. That becomes more difficult near a warm front because IMC can be so widespread.

Airports with high approach minimums, limited weather reporting, and limited approach facilities are poor choices for an alternate. When youve decided that things have decreased enough at your destination to go to your alternate, you definitely want everything stacked in your favor.

One of the advantages to flying on an IFR flight plan is that you will maintain constant contact with ATC and if the weather begins to drop near your destination, you may get a heads-up from ATC.

Another advantage is that youre already working within the system, so that if the weather gets bad, you wont be denied flight following or other services. If you are VFR, you need to call flight service to get regular weather updates, and if the weather starts dropping, you may have to file an IFR flight plan en route.

Sometimes you can pop up and a gracious ATC controller can work up an instant IFR clearance for you, but dont count on it. If you are trying to get a clearance due to worsening weather, ATC is already very busy because they are handling an extra workload due to the traffic delays caused by the weather. Holding instructions and aircraft needing to divert for fuel are really going to tie up the radio.

Ground Speed Calculations
During your preflight briefing, you will receive a winds aloft forecast. Take the time to work up some ground speed estimates. While en route, occasionally compare your actual ground speed with the predicted ground speed.

This will give you an early warning if your performance is different enough from the plan to require corrective action and it allows you to start formulating a plan to deal with unexpectedly slow ground speed.

Use your GPS to monitor ground speed and estimated time of arrival, and pay attention when reality starts diverging from the plan. Better to start considering your options before you get too far down the road. Dont wait for things to get better. Its much easier to take a 30-minute fuel stop than to be in the air watching your fuel gauges and worrying how much fuel you have left.

Know Your Airplane
On a long trip, knowing your airplanes performance is even more critical, since small errors in fuel burn calculations and time en route are magnified by the distance. You need to know the airplanes climb and cruise performance, especially how it differs from whats printed in the flight manual.

In almost every airplane, fuel consumption will be slightly higher than book and airspeed will be slightly lower.

Lets say youre planning a 500 mile trip and the POH says the airplane cruises at 125 knots at 7 gallons per hour. The POH predicts a flight time of 4 hours for a total fuel usage of 28 gallons. With a 30-minute VFR reserve, that means a total fuel requirement of 31.5 gallons. If, however, the aircraft actually cruises at 115 KTAS with a fuel consumption of 8 gallons per hour, the trip will take 4 hours 20 minutes and 34.7 gallons. See what happened to your fuel reserve?

Many real world aircraft use up their planned fuel reserves while en route. Even a simple leaning mistake can lead to dramatically higher fuel consumption. Without fuel reserves, you are stuck with no options at your destination – presuming you even make it that far.

Before taking a long trip in the aircraft, do a little research. Begin your preflight by filling the tanks to the point you plan to fill them: topped off, to the tabs or to the bottom of the filler neck. Load the aircraft to a weight that closely resembles what you plan to fly with during your long trip.

Take off and climb to the same altitude you plan for your long trip, and do the takeoff and climb while using the fuel from just one fuel tank. Switch fuel tanks when youre established in cruise and fly for a while.

When youre ready for descent, switch back to the tank you used for the climb. When you get back on the ground, refuel to the point where you started, and youll get a fairly good indication of the fuel burn for climb and descent as well as for cruise. Compare those numbers with the POH charts and you may be surprised at what youve been taking for granted until now.

Ready for the Big Day
If you plan your flight well, get a full weather briefing, plan the fuel usage well and know your alternates, youll be ready for the trip. Plan to give yourself enough reserve for the what ifs.

Never plan a trip to the maximum range of your aircraft, because a real world aircraft just isnt going to match the performance of the POH. Dont expect to extract maximum performance out of yourself, either. Excitement or nervousness over the trip may leave you a bit tired when you start out – just think of what youll feel like after two 400-mile legs.

When unexpected delays start happening enroute, dont be shy about making a precautionary fuel stop. You should plan your trip so that you have good access to fuel along the way for just such occasions.

Keep up with the weather enroute. While it sure is pleasant to fly with no radio noise, there is also a comfort in flying within the IFR system and knowing that if you start having a problem that youll instantly have ATC help.

Remember that long flights mean you are sitting around for a long time. Your legs may stiffen and your behind will ache because of the lack of movement. Your mind can wander while you are droning along. Schedule some breaks so that you can get out of the aircraft and stretch your legs.

Plan the trip so that you fly near airports with good facilities – nav aids, fuel, hotels, food and other services. In much of the west, that isnt possible. In that case, consider a route that will keep you closer to civilization.

Usually a long trip means maximum fuel and perhaps some baggage. Do a good weight and balance calculation. Remember that your takeoff and climb performance will suffer with heavier loads. Your fuel consumption will also increase when flying with a heavier load. Getting up to altitude will take longer than during your short local flights.

Dont pressure yourself with time limits or get-there-itis. Remain flexible. Remember that you fly general aviation aircraft because it is supposed to be fun.


-by Patrick Veillette

Patrick Veillette, with a fondness for J-3s and the keys to a Boeing, has amassed more than 15,000 hours.

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