"ILS" approach C182

[Great Ozzie]

cessnalover,

Below limitations come out of a POH for a C172R w/ the KAP 140. I would suspect similar limitations for the KAP 140 equipped C182.

5. The system is approved for Category I operation only
(Approach mode selected).

6. Autopilot maximum airspeed limitation -- 140 KIAS.
Autopilot minimum airspeed limitation -- 70 KIAS.
Autopilot minimum approach speed -- 80 KIAS.

7. Maximum flap extension -- 10°.

8. The autopilot must be disengaged below 200 feet AGL during
approach operations and below 800 feet AGL for all other
phases of flight.


As molleh alluded to, difficult for me to imagine a GA airplane of this sort with Autoland capability. But I did find a couple articles that reference the (future) possibility.

Diamond to offer auto landing in 2016 (AOPA)
GA Fly-by-Wire: Diamond Says Three Years (AVweb)

Aurora Flight Sciences announced today that it has successfully demonstrated fully autonomous takeoffs and landings (ATOL) on a General Aviation aircraft. (Aurora Flight Sciences - 06.29.2009)

-Rob

[AKar]

Some of the limitations from KAP 140 supplement from the POH that can be found here. Note the airplane the POH applies is equipped with G1000 cockpit, but has the same KAP 140 that we do, so some bits may differ.

• • The system is approved for Category I operation only (Approach mode selected).
  • Autopilot maximum airspeed limitation - 160 KIAS
  • Autopilot minimum airspeed limitation - 80 KIAS
  • Maximum flap extension - 10°.
  • The autopilot must be disengaged below 200 feet AGL during approach operations and below 800 feet AGL for all other phases of flight.
  • Manually overiding the autopilot to change pitch or roll attitude is prohibited (Disengage the autopilot before moving the control wheel manually).

So they are quite similar to 172R. I recall seeing a placard somewhere (AMM?) that prohibits AP use with flaps extended. Not sure to which installation that was applicable however.

Interesting links that Rob posted. I'd imagine there are some difficulties implementing an autoland to a small plane, as the landing technique is entirely different to big stuff. Airliners are just about always landed with the wing producing significant lift, and still far from the maximum CL. They are just pitched up a bit to kill the vertical speed and flown into the runway - an easy maneuver for (auto)pilot! That's why the spoilers are important in those things. I understand from conversations that at least in 737 the autoland usually makes a really 'positive' touchdown, and some pilots actually avoid using it for passenger comfort, conditions permitting, even in bad visibility. It helps to avoid hydroplaning, but many GA landing gear would not be up to the beating. GA planes are instead, as our good flight instructors here tell in many threads on the subject, landed at the edge of stall. I'd imagine it could be problematic to create an autopilot that would hold the airplane in level flight nicely, reliably and predictably at 0.5 inches above the runway as we students do manually all the time - right!


-Esa