Cessna 182S

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Cessna 182
Cessna 182.jpg
Type Civilian aircraft
Author(s) Stuart Buchanan
FDM JSBSim
--aircraft= c182
Status Early production
 FDM Stars-3.png
 Systems Stars-3.png
 Cockpit Stars-2.png
 Model Stars-4.png

The Cessna 182 Skylane is an American four-seat, single-engine, light airplane, built by Cessna of Wichita, Kansas.

Development status/Issues/Todo

Outside

Cockpit instruments can be seen through the aileron
This is presumably not aircraft-specific; see the Z-buffer burn-through item on the project-wide Bugs page.
no cockpit light at night visible
no pilot or copilot visible
wings are not textured
aircraft has no shadow
The model has no landing light
This detracts only slightly from the realism of the landing, because at touchdown attitude, the pitch attitude is so high that the landing light is pointing way up in the air; therefore almost anything that could possibly be lit up by the landing light is blocked from view by the cowling. A privately-owned aircraft is not even required to have a landing light, even when being operated at night. Landing with burned-out landing lights is no big deal ... assuming the runway-edge lights are working. The so-called landing light is mostly just a taxi light. The only part of the landing where the landing light is really useful is for reading the big painted number on the runway, to confirm that you aren't landing on the wrong runway.

Cockpit

Call-sign placard on panel does not match tail-number on fuselage.
No outside-air-temperature gauge.
No audio panel.
No fuel-and-weight dialog.
The menu item for this is greyed out, i.e. unusable.
The 2D cockpit instruments are visible through the 3D yoke.
This is another example of "burn through".
Can't hear sound when pressing the switches and levers in the cockpit.
No elevator trim control, nor even elevator trim indicator.
As a workaround, you may find trim indications on the location-in-air popup.
No rudder trim conrol or indicator.
No rudder pedals.
Cockpit instruments look flat.
They don't have a 3d look. The cockpit is not textured
No "flags" on the instruments.
Either the instruments need fixing, or the aircraft needs to use better instruments. The GS needle goes to mid-scale if there is no valid signal. That'll kill you for sure. I'm told that the hi-res instruments implement flags, but the lo-res ones don't, and the c182 model is using the lo-res versions.
hsi does not properly respond to the instrument failure popup.
This is not specific to the c182.

General

The model doesn't implement cowl flaps.
This affects the realism, especially if you are using the model for "transition training" into complex aircraft. Cowl flaps are part of the workload that makes the thing complex. Also they underline the point that the checklist that works for one aircraft doesn't necessarily work for them all.
Oil pressure problems.
In the model, after flying for a while, the oil pressure falls below the bottom of the green. Not by a lot, but definitely outside the green range, and therefore outside the normal range. Is this perhaps because somebody forgot to open the cowl flaps? This detracts from the realism; most pilots would be very unhappy flying an aircraft with out-of-normal oil pressure.
Unrealistic adverse yaw.
In cruise, the model has much more adverse yaw than a real Skylane. The real thing has differential aileron deflection which the designers have lovingly tuned so that you can cruise with your feet on the floor (not on the pedals). At low airspeeds, of course, the real aircraft still has plenty of adverse yaw.
Unrealistic damping, or lack thereof.
Compared to the real aircraft, the model seems to have not enough yaw-wise damping and not enough roll-wise damping. (Taken together these imply not enough damping of the Dutch roll mode, but this is a corollary, not a separate issue.) Roughly speaking, this creates the impression that the model is harder to handle than the real aircraft.
Engine sound in cockpit does not differ from outside engine sound.
Bad "reset" behavior.
Aircraft is sometimes flipped when pressing the reset button.
Aircraft has the wrong elevation (approximately 20 meter above the runway) after pressing the reset key
Flaps/power/trim interaction.
The C182 model does not realistically capture the flap/power/trim interaction. In the model, extending the flaps seems to cause a nose-down pitching moment, which is the wrong direction. And the power-dependence of the effect is not realistically modelled. In a real C182 / C172 / C152 / C150, the flap/trim interaction can be described as follows:
  • Changing the flap setting has little effect when the engine is at idle.
  • Changing the power setting has little effect when the flaps are in the retracted position.
  • However, there is a multiplicative effect: Adding power causes a nose-up pitching moment when flaps are in an extended position. Or, to say the same thing, extending the flaps causes a nose-up pitching moment. The effect is in proportion to the amount of power being developed *times* the amount of flap deflection.
The model seems never to consume any fuel.
A dump of the property list indicates that engines/engine/fuel-flow-gph takes on reasonable values and tracks the throttle setting, while engines/engine/fuel-flow_pph remained stuck at zero. This is a particularly bad disconnect, since apparently the latter is what gets integrated to calculate engines/engine/fuel-consumed-lbs.
Unrealistic brake noise.
While sitting on the runway, whenever the brakes are applied the aircraft makes faint scratching noises, and bobbles a little bit in pitch ... even if the engine is off! With the engine off, I can't imagine why applying the brakes would cause bobbling. This applies equally to the parking brakes, plain old service brakes, and either (or both) toe brakes. This is observed in the C172r and C182 models and perhaps others (but not the PA24-250).

Non-bugs

Tumbled attitude indicator.
The horizon instrument is in wrong position after doing some wild flying maneuvers. This is a realistic model of a tumbled gyro.
Cockpit window has no windscreen wipers.
This is realistic.
hud is not available.
This is realistic.

Completed items

ailerons on the right side are not animated
cockpit area lighting, so that (among other things) the flap handle can be seen at night.
Retractible landing gear.
There now exists at c182rg model.
Tachometer
Note that on a real C182, on the tachometer, the green range tops out at 2400, and there is also a red radial line at 2400.
In the model, the markings are wrong. The red radial line is absent, and the green goes all the way up to 2500. (The model's propeller governor is properly set, limiting the revs to 2400.)
Engine sound.
In the model, the engine noise is was the same at all speeds from 1500 RPM on up. (The pitch gets lower as the speed drops below 1500 RPM.) This has an impact on pilot technique; the pilot should be able to hear RPM changes, anywhere in the range. This is particularly significant when doing the preflight magneto check at 1700 RPM.
Pilot seat.