It's individuals, not corporations, who dominate orders for new business jets. Many — probably most — of those jets will be flown by professional crews, but increasing numbers will be piloted by their owners at least some of the time. That means hundreds of pilots will transition from some sort of propeller-driven airplane into a jet for the first time this year.
There are several types of jets that can be flown by a single pilot instead of a crew, and that holds additional appeal for the airplane owner who is freed from the complications and expense of having to take a copilot along. The Beechcraft Premier IA, the CitationJet series, the Mustang and the Embraer Phenom 100 are just some of the jets eligible for single-pilot operation. And more are in development.
So what's the big deal about jets? Why do the FAA, insurance companies and especially pilots view them as different creatures from propeller airplanes?
Some of the mystique is left over from the early jet age when our understanding of aerodynamics, particularly at high altitudes and high airspeeds, was not complete. Early jets did have many characteristics, such as the so-called "coffin corner," that could trap the inexperienced pilot. The "coffin corner" is largely a thing of the past, but in early jets the wing design was such that, at a high altitude and high weight, the jet could be flying just a few knots above the low-speed stall buffet, and just a few knots below the high-speed Mach buffet. In that situation, turbulence or the added load of aggressive maneuvering could put the airplane out of control.
Another reason a higher level of pilot training and experience has been demanded for jets is that they are certified to a higher standard of potential safety than propeller airplanes are. From takeoff to touchdown there is not a single failure, or even a series of aircraft or system failures, that is remotely possible that would prevent a jet from safely reaching a runway. But to make use of these redundant capabilities, the jet pilot has to perform to a high level and react correctly to each system failure or potential emergency. If the pilot isn't up to the task, the greater potential safety of the jet is squandered.
It is for this reason that the FAA requires the pilot of any jet to have a type rating in that airplane. A type rating, as the term implies, means that a pilot is rated to fly that specific type of jet. That differs from the requirement for propeller pilots to have a category rating, such as single-engine land, or multiengine land and so on. A type rating applies to a specific jet, such as a CE-525 (CitationJet), and, no matter how much experience you have in that type, it doesn't carry over to another type of jet.
But are jets really that different to fly? Does a pilot need different techniques than in a propeller airplane? Again, the answer is yes, but also no.
I think that most pilots new to jets are surprised, at least a little, by the time it takes the engines to spool up or down, and by the amount of power available.
The certification rules allow a jet engine to take as long as five seconds to accelerate from idle to maximum power. You may think five seconds is brief, but just try counting those seconds out as you wait for a full response to your power-lever movement. If you are already flying too slowly and need more power, a lot can happen in five seconds, and none of it will be good.
On your first few takeoffs in a jet, you will notice the lag in engine acceleration, and thus airplane acceleration, as you advance the throttles. But then you will also be surprised by the acceleration of the acceleration, if that makes sense. The power response from a jet engine is not normally linear. In other words, as the engine compressor and turbine start to spin faster and faster, the thrust is multiplying. So, if it takes four seconds for an engine to reach full power, more of that power will be produced in the last second or so than in the first three.
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Single-Pilot Jets? When a manufacturer requests single-pilot approval for a jet, the FAA has a committee of inspectors fly the airplane. If the FAA pilots determine that all essential controls, switches, breakers and so on are within clear view and reach of a single pilot, and also find the workload acceptable, they will approve the request. A manufacturer can design for single-pilot operation, and seek guidance from the FAA during development, but won't know for sure if it will be granted until the airplane is complete. If the airplane is eligible for single-pilot operation, the pilot must be trained and checked to fly it by himself. The requirements for flying precision and performance are the same for the single pilot as for a crew, and examiners take a very hard look at how the pilot handles emergencies as well as how he flies under normal conditions. Most pilots new to jets are encouraged to earn the crew type rating first and gain experience in the airplane flying with a qualified pilot in the right seat. In reality, insurance companies are going to demand that a new jet pilot log some hours with a mentor, so the type rating isn't that big of an issue. Once a pilot is comfortable flying as a crew member, he can return to the training center and, after some practice handling the airplane by himself, take a check-ride solo and have the (S) added to his certificate, signifying he's qualified for single-pilot flying. Flying without a copilot is very convenient on the ground, where there are no issues of what to do with the other guy while you spend time in meetings, with the family or whatever. But in the air, you need to be aware that you are sacrificing at least some amount of potential safety. Jets have backup systems for every conceivable failure, but if the only human in the cockpit has no backup, those redundant systems won't be of any use if the human fails to perform properly. |
As you accelerate down the runway, the jet engine is feeding itself more air and thus increasing power output. This is called "ram recovery" because the slipstream air being rammed into the front of the engine is helping the compressor do its job. This phenomenon was even more noticeable in old straight turbojet engines that really got to work when the airspeed hit 200 knots or more, but it is still noticeable in modern turbofan engines in which the fan produces the big majority of thrust at low airspeeds and low altitudes.
At takeoff rotation, the jet has a huge excess of thrust because every takeoff is planned to be able to continue safely if one engine fails at the worst possible time on the runway. This excess thrust will amaze you at first because, unlike conventional propeller airplanes, the jet will both climb and accelerate with the nose up at a high angle. Pilots with only propeller airplane experience will be tempted to release back pressure on the yoke after rotation, but that will only allow the jet to blow through the 200-knot airport traffic area speed limit. In reality you will need to hold the rotation angle, maybe even increase it, and then reduce power a lot if you have an assigned level-off a few thousand feet above the airport.
