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Flying a C162 I have to set nose down trim to maximum, but I still feel pressure on the control and need to push the nose down. Is this expected, or is weight & balance near the limit of the plane?

I checked the weight & balance and the CG is within limits but total weight is close to max gross takeoff weight.

Edited to add:

Weight & Balance info: (bracket indicated values that were used)

  • Basic empty weight 866.85, CG 131.97
  • Pilot (180), Arm 142
  • Pax (170), Arm 142
  • Fuel (80), Arm 143.26
  • No Baggage

CG location computed as:

  • Zero fuel weight 1217 lbs, CG at 134.7 ish
  • Takeoff weight 1289 lbs, CG at 135.3

I experienced residual control force at TAS around 80-100 knots.

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    $\begingroup$ At what speed in the airplane's speed range? $\endgroup$
    – John K
    Aug 11, 2022 at 5:06
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    $\begingroup$ Stupid thing cruises at 110+kt and should trim to any speed up that speed. There is no way the thing should require forward pressure to operate at cruise speed at full ND trim. Something is bent, or the tab gearing is out of rig. Or, it's just a crappy airplane. I wouldn't want one. $\endgroup$
    – John K
    Aug 11, 2022 at 23:00

2 Answers 2

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It sounds as though the basic empty weight and moment calculated by maintenance personnel is not quite correct. A Cessna 162 Skycatcher is certified under FAA FAR Part 23.

§ 23.2140 Trim.

(a) The airplane must maintain lateral and directional trim without further force upon, or movement of, the primary flight controls or corresponding trim controls by the pilot, or the flight control system, under the following conditions:

(1) For levels 1, 2, and 3 airplanes in cruise.

(2) For level 4 airplanes in normal operations.

(b) The airplane must maintain longitudinal trim without further force upon, or movement of, the primary flight controls or corresponding trim controls by the pilot, or the flight control system, under the following conditions:

(1) Climb.

(2) Level flight.

(3) Descent.

(4) Approach.

(c) Residual control forces must not fatigue or distract the pilot during normal operations of the airplane and likely abnormal or emergency operations, including a critical loss of thrust on multiengine airplanes.

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Trim tab setting determines the angle of attack at which static stability forces in pitch (weathervaning tendency, in effect) will stabilize the plane hands-free.

As a proxy for angle of attack, pilots use indicated airspeed, since at a given C of G position and loading, a given angle of attack is found at a specific airspeed.

Although Part 23 is a bit vague with respect to trim speed in level flight, with G of G and total load in limits, the airplane should be able to trim hands-free to its normal cruising speed, or you have "residual control forces" which make the airplane unpleasant and distracting to fly at that speed.

So, if the plane can't be trimmed to its normal cruise speed, and C of G and loading is in limits, it's reasonable to suspect a problem with the trim rigging.

If the rigging and C of G and loading is good, then you are stuck with a plane that can't trim to its cruise speed, which is pretty strange. Your only option if you want hands-off stability is to reduce power to the speed at which the plane will fly level hands off, and use that as your cruise speed.

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  • $\begingroup$ It is a Part 23 requirement to be able to trim at all CG ranges inside the envelope. $\endgroup$
    – wbeard52
    Aug 11, 2022 at 23:49
  • $\begingroup$ As the other posted answer with the quote from Part 23 says, just "level flight", which is open to interpretation. An airplane that can't trim to its cruise speed + some margin is a useless piece of equipment as far as I'm concerned. I've never experienced that, except in the case of a couple of homebuilts I've flown that had only fixed tabs, and therefore only one trim speed, and if you wanted to fly faster than the speed the fixed tab set, you had to hold forward pressure.I can't believe the Skycatcher is like that, but maybe that's one of the reasons they dumped the project after a few a/c. $\endgroup$
    – John K
    Aug 12, 2022 at 4:02

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