by Jonathan M. Stern
Corporate Jet Checkout
When it comes to having a sense of sitting on top of the world, there's nothing quite like flying in, or flying, a corporate jet. The Lear 35A, which comes standard on Flight Simulator, may be selected from the Options/Aircraft menu. The Lear performs in many respects like the Cessna 182RG, except that it is significantly faster, climbs significantly higher, and is larger. Some of the specifications of the Lear 35A follow:
|Engines||2 Garrett TFE731-2-2Bs (3,500 pounds each)|
|Length||48 feet 8 inches|
|Height||12 feet 3 inches|
|Wingspan||39 feet 6 inches|
|Wing Area||253.3 square feet|
|Maximum Ramp Weight||18,500 pounds|
|Maximum Takeoff Weight||18,300 pounds|
|Standard Empty Weight||9,838 pounds|
|Maximum Landing Weight||15,300 pounds|
|Wing Loading||71.1 pounds per square foot|
|Power Loading||2.61 pounds per pound of thrust (at maximum takeoff weight)|
|Service Ceiling||45,000 feet|
|Maximum Usable Fuel||925 U.S. Gallons|
|Maximum Operating Speed||0.81 Mach|
|Economy Cruise (45,000 feet)||418 knots TAS|
|Maximum Cruise Speed (at 41,000 feet)||460 knots TAS|
|Maximum Rate of Climb at Sea Level||4,340 feet (at maximum gross weight)|
|Approach to Landing Speed||128 knots|
|Stall Speed Flaps and Gear Down||96 knots|
The Lear uses a different instrument panel and has different engine instruments than the Cessna (see Figure 7.8).
Figure 7.8. The Lear 35A inside and outside.
Table 7.1 contains a comparison of the flight instruments in the Lear 35A with the flight instruments on the Cessna 182RG.
The difference in engine instrumentation results from the fact that the Lear is equipped with a pair of turbofan engines. A turbofan engine combines qualities of a turbojet engine with a propeller, Air is drawn into the front of the engine by a fan, which is much like a propeller. A substantial percentage of the air is ducted around the engine's compressor section and combustion chambers and is pushed out of the rear of the engine through the propelling nozzle.
The portion of the air that is not ducted passes through a compressor section, which compresses the air, significantly increasing the pressure of the air. It then mixes with fuel entering the chamber through fuel injectors and is ignited in the combustion chamber. The rapidly expanding gases leaving the combustion chamber pass through a turbine, which spins both the fan and the compressor blades at the front of the engine. After passing through the turbine, it too is pushed out the propelling nozzle. The combination of the ducted air and the ignited air provides the thrust of the engine.
With the exception of a digital readout of turbine and fan speeds for each engine, the engine instruments are on a separate panel accessed by pressing the Tab key (see Figure 7.9).
Figure 7.9. The Lear's engine instrument panel is accessed by pressing Tab.
|TABLE 7.1 The Lear 35A Versus the Cessna 182RG|
|Instrument||Lear 35A||Cessna 182RG|
|Airspeed Indicator||Provides an analog readout to 450 knots and a digital readout at higher speeds; no color codings to reflect certain V-speeds or operating ranges.||Displays airspeeds from 40 to 200 knots; uses color coding to indicate certain V-speeds and operating ranges; calibrated in 5 knot increments.|
|Attitude Indicator||Electronic flight instrument system (EFIS)—uses a CRT to display attitude information with bank angles of 0, 10, 20, 30, 60, and 90 degrees depicted and pitches of 5, 10, 15, and 20 degrees depicted.||Uses conventional analog instrumentation to display the same information; in the real airplane, the height of the model airplane may be adjusted to overcome a parallax effect (a control unnecessary with a CRT display).|
|Altimeter||Uses a sweep hand to display hundreds of feet with a digital readout of actual altitude.||Uses a three handed display to provide an analog readout of altitude.|
|Heading Indicator||Heading is displayed digitally; the compass card that forms a background does not even rotate; may be calibrated by pressing D.||Rotating compass card displays current magnetic heading; may be calibrated by pressing D.|
|VOR/ILS Display||This EFIS display provides the VOR/ILS and DME display for the NAV 1 and NAV 2 radio or the ADF display; it may be toggled between displays by pressing Shift+Tab.||Analog display of both NAV radios simultaneously or NAV 1 and ADF; toggle between NAV 2 and ADF by pressing Shift+Tab.|
|Vertical Speed Indicator||Displays vertical speed in thousands of feet per minute with instantaneous readout.||Displays vertical speed in hundreds of feet per minute with readout lagging by approximately six seconds.|
|Angle of Attack Indicator||Displays the angle of attack with a critical area in a yellow zone.||Not available.|
|Spoiler Position Indicator||Shows whether spoilers are extended (in use) or retracted.||Not available.|
Instrumentation for the Lear's engines displays turbine speed and fan speed, each expressed as a percentage of maximum, turbine temperature in degrees Celsius, oil temperature and pressure, and fuel flow in pounds per hour. A total fuel quantity gauge is provided, although the fuel in each tank can be determined by selecting the Sim/Engine and Fuel menu.
The engine starting procedure for a jet engine is simplified in the Lear with an automated system. When the Lear 35 is selected, the engines are already running. If you want to run through the startup procedure, take the following steps:
- Shut down both engines by pressing Ctrl+Shift+F1. This stops the flow of fuel to the engines.
- Press Ctrl+Shift+F4 to restart the flow of fuel.
- Start the left engine by pressing STR under L with the mouse or by pressing E, 1, J, +. By pressing E followed by 1, you select the number one engine, which is the left engine.
- Start the right engine by pressing STR under R with the mouse or by pressing E, 2, J, +.
- If you used the E, 1 or E, 2 keys, restore simultaneous control of both engines by pressing E, 1, 2.
Note that, with version 5.0, engine sounds are associated with only the left engine. The right engine, whether on or off, remains silent.
Because jet engines are fuel injected, there are no carburetors and, therefore, no carburetor heat. Power operation is also substantially easier than with the Cessna 182RG, because it consists solely of a pair of throttles. Because there are no propellers, there are no propeller controls, and because fuel/air mixtures are automatically adjusted, there are no mixture controls.
Spoilers, which, as discussed earlier in the book, spoil lift and allow higher rates of descent without as much airspeed, are controlled either with a mouse click on the spoiler indicator box or by pressing the slash (/) key. Spoilers are also used after touchdown to spoil any lift that might otherwise reduce the effectiveness of brakes and to create drag to help slow the airplane.
Additional speed reduction after touchdown is provided through use of thrust reversers, which reverse the direction of thrust from the engines. Thrust reversers are engaged in Flight Simulator by holding down Keypad 3 until both throttles are at the lowest point in their travel (in the red zone). Alternatively, the thrust reversers may be engaged by holding down the F2 key (F8 key for keyboards with function keys on the left side) until the throttles are at the bottom of their travel in the red area indicating reverse thrust.
To return to idle normal thrust, press Fl or press Keypad 9 until the throttle position indicator returns to idle. Thrust reversers should usually be disengaged when airspeed slows to 60 knots in the landing roll. Unfortunately, thrust reversers are not accessible in Version 5.0 with certain throttle equipped joysticks and control yokes. The airplane can, however, be flown and landed without thrust reversers. In fact, in some corporate jets thrust reversers are optional.
The engines on the Lear are individually controllable. For example, it is possible to start one engine and make a complete flight on only that engine. Controlling a multi-engine airplane with only one engine operating is not easy, however, and it is almost never done from the takeoff. Single engine approaches and landings, however, are part of the training when transitioning into any multi-engine airplane. In addition to the lack of power, thereby reducing climb and speed capabilities, the fact that the thrust is produced asymmetrically creates control difficulties that must be dealt with through special techniques. It is beyond the scope of this book to address these techniques and procedures. If, however, you wish to try it, you may do either of the following steps to simulate the loss of an engine.
To shut down an engine:
- Select the engine you wish to fail by pressing E, 1 for left engine or E, 2 for right engine.
- Press Ctrl+Shift+F1 to stop fuel flow to the selected engine.
- To restart the failed engine, press Ctrl+Shift+F4 to restore fuel flow to the failed engine.
- Press J,+ to engage the starter for the selected engine.
- Press E, 1, 2 to restore simultaneous control of both engines.
To reduce one engine to idle power:
- Select the engine on which you wish to reduce power by pressing E, 1 for left engine or E, 2 for right engine.
- Use any keyboard technique for reducing throttle to idle; only the selected engine is affected.
- To return to normal power, adjust the throttle to the same power level as the other engine.
- Press E, 1, 2 to restore simultaneous control of both engines.
Table 7.2 contains some tips for flying the Lear 35A.
|Table 7.2 Tips for Flying the Lear 35A|
|Use a light touch on the controls||The Lear is a highly-responsive, fast-moving airplane; it is easy to over-control it.|
|Observe operating speed limitations||Overspeed can lead to loss of control or structural damage; published performance figures such as required runway lengths depend on use of proper speeds.|
|Anticipate the need for more power||Turbine engines take more time to react to changes in throttle setting (to "spool up") than do reciprocating engines.|
|Use runways of sufficient length||Generally, the Lear should not be operated on runways shorter than 4,000 feet. Properly use thrust reversers and brakes during landing roll out.|
|When making a tight turn while taxiing, use differential braking and differential power||Using the left brake and right throttle yields the tightest left turn that the airplane can make; be careful not to lose control.|
Note: Approaches: Maintain 130 knots on final approach. Gear extension/retraction: below 200 knots. Flap extension: 8 degrees—200 knots; 20 degrees—185 knots; 40 degrees—150 knots. Maximum Speed: Mach 0.81 (unfortunately, the Flight Simulator Lear does not display Mach speeds).