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Hands-off trim pseed and emergency landings in the 260se

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  • Hands-off trim pseed and emergency landings in the 260se

    There is a noticeable difference in some 260SE's
    when it comes to a hands off trim speed. This is
    almost always due to avionics. A very full panel
    (especially of the older variety) will contribute to this
    situation. Also you must keep the right speed and a proper
    rate of descent with a little power to have it all
    trimmed up properly. Normally with two people in the
    front (most fwd CG) the 260SE should trim hands off
    pretty well at 55 kts when properly flown. Our 260SE's
    will actually trim hands off down around 50 kts.
    40 degrees of flaps works well if you need a steeper
    approach but the added drag will normally defeat the
    purpose of having a high lift low drag airplane like the
    260SE. Going to 40 is also of no benefit in reducing the
    actual touch down speed although it does allow you to
    hit a spot just a little easier if speed conrtrol is
    a problem. I use the flaps just like the throttle
    in that I may lower flaps to 40 then retract them to
    20 on approach. I have also found that 30 degrees of
    flaps works really well. It gives just a little bit
    more drag (which makes speed control easier) but it
    doesn't induce so much drag that a go around is a
    problem. The real key to having a slight amount of
    power in the flare is the speed. If you start the round
    out for flare at 65 kts. any power will probably be
    too much. But at 50 to 55 kts a little power will be
    required. Normally I always recommend that when learning
    how to fly a slow approach it is best to have a
    competent pilot beside you to help out with tips at the
    proper moment. It's kind of like flying instruments. You
    could probably learn everything you need out of a book
    with some self taught flying but it is no substitute
    for having a good instructor teaching you. As I am
    sure "grasshopper" will agree some of the things we are
    talking about can deteriorate quickly if the pilot is
    behind the airplane, likewise some of the techniques are
    really small and very delicate. I have also
    developed a procedure for an emergency landing that may
    prove helpful for some of you. Assuming you are at
    altitude when the engine stops you will logically set up
    best glide speed and try to get the max distance with
    the flaps up. Try to arrive over your spot of
    intended landing with a lot of altitude or set up a final
    straight into a field with a lot of altitude. I begin the
    actual approach with 20 flaps at 60 kts with an approach
    that will overshoot the field. When getting in close I
    then go to 40 flaps and slow to 55 kts. With the flaps
    at 40 you can almost point the airplane at your
    intended landing spot without building too much speed. This
    eleminates the very common problem of undershooting your
    intended touch down point. If you do end up with too much
    speed during the flare the 40 flaps gets rid of it
    quickly. It is then important to make a full stall when
    touching down. It does no good to have an airplane that
    lands at 35 kts if you drive it on at 50 kts. Be sure
    to review the emergency checklist every now and then
    so you know what to do with the cabin doors, fuel,
    etc. Todd
    Kevin Moore
    Former 260se/stol Katmai with BRS owner; planeless for now
    sigpic

  • #2
    During a rare half-day gap in an otherwise
    continuous two-week storm onslaught I was able to fly this
    morning, and used the time to practice some simulated
    engine-out approaches and landings. I had as a comparison
    some similar training in the Cirrus SR20 a little over
    a month ago. Interestingly, both planes have about
    the same glide ratio, 11:1. However, Vg for the 260se
    is ~70 KIAS, while for the SR20 it is 94.
    Despite the nearly identical glide ratios, the experience
    is very different. In the SR20 things happen very
    fast, your descent rate approaches 900 fpm at Vg, and
    the pilot needs to make quite prompt judgments &
    decisions (i.e., turn towards the runway NOW you idiot, or
    eat a dirt sandwich). In contrast the 260se's Vg
    descent is at a more leisurely ~650 fpm and the pilot has
    more time to assess and modify glidepath by slipping,
    deploying/retracting flaps, varying IAS between 55-70, etc. To
    exaggerate only slightly, it was more like, "Well, lessee,
    maybe I'd better turn base...and OK...*yawn*...I
    suppose I should turn final about now...let's bring in
    full flaps...ah yes, that's more like it, let's
    retract to 20 degrees flaps and schmooze on in at
    57-60...nice gradual flare and touchdown at 40-42..." As
    Michael indicated in an earlier post, one's tendency is
    towards overshoot, and there are a variety of tools
    available to compensate. In a more heavily wing-loaded
    plane like the Cirrus, one would without recent
    practice tend to not react quickly enough and thereby risk
    undershooting--no compensation for that! Based on both
    sessions my conclusion is that the 260se would be more
    forgiving of inexperience in such a scenario. In fact, at
    an IAS of 55-70, ~650 fpm descent, I suspect that
    one could fly it all the way to the ground in IMC,
    perhaps flaring just enough to get a mains-first
    touchdown, and likely walk away. Not that I'm very anxious
    to try the experiment...Kevin
    Kevin Moore
    Former 260se/stol Katmai with BRS owner; planeless for now
    sigpic

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    • #3
      Your post on the emergency landings got me to
      thinking about the old Wren days. The engineering we
      acquired with the Wren said the landing gear of the 182
      was good at gross (2800 lbs) to take a rate of
      descent on landing of 700 fpm without damage. As the
      power off descent rate of the Wren (and the 260SE)
      hovered at that figure or below I always figured you
      could carry the power off glide all the way to the
      ground without potentially damaging the airplane during
      the touch down (actually more of a smack
      down). Even with the wheel all the way back in a deep
      stall seldom do we see more than a 700 to 800 fpm rate
      of descent. If a person had to I think you would be
      safe slowing the airplane up to a minimum speed of
      around 45 kts then just let the airplane descend to the
      ground. Assuming you hit something reasonably flat I
      think you would not only be okay but the airplane
      wouldn't be damaged. If you hit something you'd still be
      much better off than hitting it at 60 kts or better.
      The Wren had been certified in a limited flight
      envelope at 850 lbs over gross (3,650 lbs) for ferry
      flights across the ocean. When flying at this weight the
      flaps extension speed was reduced to around 85 kts and
      the rate of descent on touch down had to be less than
      300 fpm. I can say with authority that the airplane
      flew well at 3,650 lbs although its rate of climb with
      the 230 hp engine was not all that great.
      Another real safety of flight item with the 260SE is its
      ability to fly slowly, in a flat attitude, while flying
      VFR in areas of very poor weather. Having the ability
      to slow into the 55 kt range effectively triples
      your visibility when flying in areas of poor
      visibility. I have many times flown these airplanes at
      altitudes of 200 - 300 ft with visibilities down to a mile
      or less with safety. I wouldn't recommend it but if
      you end up there being able to slow up is a real life
      saver. Todd
      Kevin Moore
      Former 260se/stol Katmai with BRS owner; planeless for now
      sigpic

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