Tale of Two Trips

Planning a flight in an airliner is much like making the same flight in a GA airplane, except its completely different

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On the FBO porch one recent Saturday morning, I sat with the rest of the airport bums critiquing takeoffs and landings when a Lance pilot really dropped it in. The considered opinion of the gathered authorities was that a touch of throttle would have saved the day.

Later, the discussion turned to big jets and how to keep one from dropping one in. Add a touch of throttle, I suggested. My jet-flying colleagues will be quick to point out that jets dont have throttles. Instead, they have thrust levers. But my point was that big airplanes operate under the same principles of physics as little airplanes.

Because the physics are the same, the vastly different safety records of big airplanes vs. little ones are a mystery to some. It shouldnt be. Airline flying is a high-stakes, high-dollar game that includes the best training, teamwork, equipment and facilities. GA flying can follow many of the same techniques. While that may not make flying a single as safe as flying an airliner, it can help bridge some of the safety gap.

Lets plan a parallel flight from Louisville, Ky., to Richmond, Va., in a 757 and a Mooney 201 to see where the operations are the same and where they diverge.

Take Flying Seriously
In just about every multi-pilot cockpit crew there exists an unspoken underlying set of expectations that each pilot will perform flawlessly. That seldom happens but everybody in the crew is always trying to do their best.

One of the most important facets of safely flying large jet equipment is the training one receives from the company that operates it. The training adheres to a yearly timetable and each crewmember is subject to a jeopardy checkride once per year and flying skills must be demonstrated at a satisfactory level. Much of the training is mandated by FARs but most successful operations know that investing in training yields worthwhile tangible and intangible benefits.

GA pilots would do well to take advantage of any available training opportunity whether it is participating in the FAA Wings program or taking part in type-training offered by many aircraft owner groups. Barring that, GA pilots can improve their chances by improving their attitude.

Dont look for an instructor to sign you off for after an easy BFR or instrument check. Demand that you be put through all the paces to very tight standards. If youre ever in the air trying to cope with everything going wrong at once, you wont be wishing your last flight instructor had taken it easier on you. Malfunctions are standard fare in airline training, with many of them coming at exactly the wrong time.

Get a Good Start
A good trip in the 757 begins with an on-time check-in for the flight. You arrive in the ready room unharried with a little time to chit-chat with your buds before looking over the paperwork. Over at the GA airport in my Mooney, the same concept applies, except the paper is mostly self-generated.

Any cross-country flight involves paperwork. In the big airplane, there is a dispatcher who is a partner with the captain and crew in planning and executing the flight. Before the captain arrives, the dispatcher has looked over the weather, Notams and delay advisories from ATC, and has come up with a proposed routing, fuel load and computer-generated flight log with estimates of distance, time and fuel calculated to the minute.

Usually the dispatcher comes up with a good plan that accounts for weather or known delays and the captain signs the flight release that indicates his agreement with the dispatcher that the flight can safely depart. This is the first in several processes where teamwork provides an opportunity for check and balance.

Most GA pilots would be surprised at the skimpy weather package airline pilots receive in their flight departure papers. A domestic flight might include only the METAR, TAF and Notams for the departure, destination and alternate airports, plus winds aloft and Sigmets and Convective Sigmets. There is no enroute weather, Airmets or Notams. But in this post 9/11 world there are tons of advisories about one security threat or another.

An old joke in the airline business is Weather? Who cares, were going anyway. With robust systems to deal with ice, the best weather radar money can buy, and a Category III autoland system, there is a grain of truth to that.

Across town, its a different story. The Mooney pilot must self-dispatch. Its up to me to track the weather, plan the flight, find Notams and flight restrictions and create a flight log.

But dont despair. A GA pilot has access to many of the same computer tools for weather briefing and flight planning employed by dispatchers. Flight Service briefers can be counted upon to provide an experienced look at the weather. They cant cancel a flight like an airline dispatcher can, but they can be an important teammate who provides key advice for the GA pilot who has to make that decision.

General aviation pilots had better care about the weather, too. Besides the fact that a light plane doesnt have nearly the performance airliners can count on for bailing them out of lousy weather, most GA airplanes spend their life down in the part of the atmosphere where the weather is the worst. Most light planes have only pitot heat for ice protection and the only practical thunderstorm avoidance tool is the eyeballs of their pilots, with maybe some help from ATC or a lightning detection device.

Not only are small planes less able to cope with rotten weather such as icing and convective activity, theyre more likely to be in it in the first place. Cutting corners on weather analysis is a false economy. But putting yourself into a situation where youre pressed for time at departure, thats exactly what youre setting yourself up for.

Departure Preparation
After the ready room, the airline pilot arrives at the 757 no later than 30 minutes prior to departure to preflight the airplane and prepare the cockpit. A fuel slip detailing how much fuel has been added is waiting in the cockpit. On most flights, airliners depart with less than full fuel and the fuel slip is used to make a simple calculation to check that the amount of fuel shown on the fuel gauges is reasonable – another check-and-balance GA would do well to adopt.

The walk-around inspection of a 757 is similar to what GA pilots ought to do with their airplanes, just on a larger scale. At an airline, the pilot flies a different tail number just about every flight, which makes it more like renting an airplane that you know receives top-notch maintenance than flying your own. Theres no way to be intimately familiar with the particular bird youll be flying, but youre confident about its airworthiness.

An aircraft mainenance logbook that records every flight and maintenance action stays with the airplane and gives the pilot a picture of the mechanical health of the airplane. The on-board logbook information goes back about two weeks, but maintenance control has records from day one.

If any mechanical discrepancies are discovered during preflight, mechanics are usually at hand to resolve them before departure. If a fix cant be made, many times the airplane flies anyway because system redundancies allow the component to be MELd which means it is deactivated or not used according to directions in the Minimum Equipment List. The MEL (pronounced M-E-L) is an exhaustively complete guide on how – or whether – the airplane can be operated with the affected equipment inoperative.

Prepping the Mooney for departure is a little different. The maintenance is less of a question because I do some of the light maintenance and write the checks for the rest. But if there is a mechanical problem, its often more difficult to get it fixed than just the simple radio call for the 757. Light plane pilots are at the mercy of unfamiliar mechanics when away from home. At the very least, it means interrupting someone elses scheduled maintenance. If its outside of normal business hours, you have the problem of getting a mechanic to come in just to look at your airplane – a time-consuming and potentially expensive proposition.

Loading the big airplane is a bit more complicated than loading the Mooney, but follows the same tradeoffs of payload and fuel. After the 757 is loaded, the flight crew is presented with a weight and balance document that takes only moments to complete. Airliner loading is made slightly more complicated by the need to balance the load with the amount of runway available – an issue that usually doesnt bring GA pilots any grief.

In a transport category jet, data are checked to make sure aircraft gross weight fits the runway available, based on temperature and altitude. If the runway is contaminated with snow, ice or slush other adjustments are made.

GA pilots – myself included – are usually a bit more cavalier about loading. I usually just eyeball the weight and balance and only crunch the numbers if I think it will be close. Ive flown the airplane long enough that I have a pretty good idea of what it will handle and how it needs to be packed.

For most departures in a light plane, takeoff performance is more or less a given unless there are some unusual circumstances, such as high density altitude or particularly short runway. In those cases, Im alert to checking the implications involved.

The airliner, on the other hand, has been scrupulously measured against the runway available for accelerating and stopping. If circumstances warrant, the airliner will be loaded up to the most the airplane can handle at that airfield rather than the most it can handle in absolute terms.

Runways and Airports
The runway has more influence on the flights takeoff than just its length. When it comes time to taxi the 757 and depart Louisville International, the citys airline airport, the crew is greeted with wide taxiways and long runways that are as level as a pool table.

All taxiway intersections are clearly marked with standard signage. The runways are crowned and grooved plus most are equipped with overruns and the departure paths are completely clear. Of course everything is lighted to the hilt.

Over at Bowman Field, where the Mooney lives, there are a few taxiways that actually are marked, but most are not. There is minimal taxiway lighting. The place is a runway incursion waiting to happen, especially at night.

One runway at Bowman has been recently rebuilt but it isnt grooved for water dispersion. None of the four runways at Bowman has the full length of pavement available for landing; all have displaced thresholds.

If you need an overrun at Bowman Field, the best you can hope for is to be using the runway where the airport fence will slow you down before you royally screw up somebodys round of golf on the adjacent course. On the other three runways, youll be a roadway surprise for some unlucky drivers.

In short, the GA airport in Louisville, as in many locales, is a red-headed stepchild that lacks the basic safety assets of its more wealthy relative. Unfortunately, if you want the best airport safety advantages in your GA airplane, you should stay away from GA airports.

Time to Fly
Once airborne, there is no comparison between the airplanes. When I first qualified on the 757 in 1990, occasionally controllers would refer to the airplane as the Atari Ferrari because of its glass cockpit and terrific performance. Its not the fastest large jet, but not many will outclimb it. The only time the vertical speed drops below 1,000 feet per minute is during climb to cruise at heavy weight above Flight Level 350.

The 757 cruises about 450 knots and burns about 8,000 pounds of fuel per hour – 1,200 gallons. If youre in a hurry and want to burn 25 percent more fuel, it will do a hair under 500 knots.

The Mooney performs like, well, like a Mooney. It cruises a little faster than most four-cylinder retracts, but its 200 horses struggle to haul it skyward at more than about 500 fpm at max weight.

At 60 pounds of fuel per hour – 10 gallons – the Mooney 201 will fly about 150 knots. For 25 percent more fuel it will cruise at just under 160 knots.

En route navigation in the 757 can only be considered fantastically precise by any standard. Provided by dual flight management computers that use radio updates to refine position information from triple inertial reference units, 757 lateral navigation devices send the airplane right down the airway centerline. The FMC also draws a moving map – technology the 757 pioneered in airline cockpits.

This is one area, however, where the airliner doesnt have the edge. The GPS and Loran navigators in the Mooney are just as accurate. In fact, the GPS database is more complete than that contained in the 757 FMC and the moving map provides more detail.

Besides the obvious speed difference, where the big airplanes like the 757 outshine GA is systems redundancy. If the engine fails in the Mooney, Im going to land soon and probably not on an airport. In the 757, an engine failure means that it will be secured and a landing made at the nearest suitable airport.

The 757 also has multiple redundant systems to operate the flight controls, landing gear and brakes. Three generators supply electrical power and any one is capable of handling the load of getting the airplane on the ground. The Mooneys redundant systems amount to a manual backup for the electric landing gear and a backup vacuum pump for the instruments.

Despite all the hardware, perhaps the 757s most crucial safety advantage is between the ears of the person sitting in the right seat. Not to take anything from my passengers – even the ones who are pilots – but a multi-crewmember cockpit, properly managed, is a thing of beauty to watch. Two sets of eyes, ears, and bodies of experience, trained to interact with each other smoothly, combine to produce a crew better than the sum of its individual parts.

At cruise in both airplanes it is just a matter of maintaining course and keeping up with weather. In the 757, our partner the dispatcher will send us text weather updates via ACARS – Arinc Communications Addressing and Reporting System – or we can request it ourselves, which is usually the case.

In this case again, the GA pilot must be proactive and find a Flight Service frequency and request the weather. During periods of bad weather, when there are lots of pilots trying to contact FSS, it can be a problem to get their attention. But even then you may be able to glean some information from the briefers comments to other pilots.

Enroute, the only weather that causes concern for the 757 is thunderstorms, and the weather radar usually makes easy work of avoiding them. A 100-mile deviation for thunderstorms takes only a few extra minutes. At cruise altitude, ice is simply never a factor. Only during flight at low altitude in the terminal area is airframe ice a concern.

Meanwhile, the Mooney slugs it out down in the worst of the weather with only the crudest of systems to deal with it. A 100-mile weather deviation in the Mooney takes 40 minutes, which opens up all kinds of temptations for the pilot to push closer to the lousy weather or stretch fuel reserves. In addition, those temptations happen with no co-pilot to serve as a check on the pilots decisions.

Approach and Landing
Getting both airplanes down from cruise altitude takes a little planning. I like to hold some power in the Mooney during descent rather than pulling it to idle. In a 757, pulling the thrust levers to idle is required if you dont want to start down 250 miles out.

In the old days – 10 years ago – pilots determined how many thousand feet they had to descend and used a multiplier to determine the distance out to start down. A fudge factor of a few miles was added or subtracted to compensate for winds or speed reductions. Some pilots still do that, but technology makes such calculations a snap.

In the 757, you tell the computer at what point you want to be at what altitude and it plans an idle thrust descent – calculated to within 10 feet and 0.1 nautical mile. It even takes in account level segments required for speed reductions. If the crew takes the time to plug in the information, the computer will plan for the application of engine anti-ice, which causes the engines to idle at a higher thrust level, and for winds aloft that dont decrease with altitude.

But even with the precision of the computer, I still make a rough top-of-descent calculation in the 757 as a reasonable check of the machine. The couple times this check has uncovered a discrepancy, it was a result of a crew error entering data.

The Mooneys GPS navigator has a VNAV function that works reasonably well but, just like the 757, its not a show stopper if I dont use it.

On vectors for approach in both airplanes, the crew must set up the cockpit and briefing the approach. Here the two-crew 757 has an advantage. The pilot-not-flying sets up the cockpit for the approach while the pilot flying gives his full attention to the task of flying. The Mooney pilot must divide his attention.

If the visibility is reported below approach minimums, the 757 crew decides whether to hold for better weather or divert to the alternate. The Mooney pilot is free to take a look-see, which may account for some of the increased number of accidents on instrument approaches in GA airplanes. Any time an airplane is near the ground and in the clouds, the potential for accident rises exponentially.

While close to the ground, the 757 has a giant safety advantage in its Enhanced Ground Proximity Warning System (EGPWS). The enhanced ground prox takes position information from the FMC and compares it to a digital terrain database. It then displays the location of higher terrain on the moving map. If the EGPWS detects that the airplanes flight path will intersect terrain, it issues warnings in plenty of time to take avoidance measures. This technology has already prevented several controlled flight into terrain accidents worldwide, including one by a U.S. air carrier.

On the approach, the 757 also has a significant advantage in avionics. The Mooney has only a single axis autopilot, directional gyro and conventional VOR indicator. The 757 has two incredibly precise flight directors backed up by three digital flight control computers and three complete autopilot systems that can guide the airplane to an automatic landing in 300 RVR weather conditions if the airport is capable.

One advantage on landing held by the Mooney is the amount of touch up work on runway alignment and approach speed that can be made after breaking out of the clouds. While it is advisable to be on speed and lined up upon exiting the clouds, the Mooney pilot still has sufficient time to make corrections. In the 757, the crew had better be lined up and on glidepath when they spot the runway or things can get ugly in a hurry.

Once theyre over the touchdown zone, a touch of throttle in either airplane will be just the ticket to a satisfying landing if the airplane is on speed, but a tad high. It will also make the airport bums giddy with happiness.


Also With This Article
Click here to view “Airplane vs. Airplane.”

-by Bill Kight

Bill Kight is a Mooney owner and a captain and simulator instructor for a large carrier.

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