30 November 2005

Birds Do It!

I love........LOVE, to get a new student that is an experienced starch-wing aviator!

All I have to do is teach them to fly the helicopter.......
they already know how to read a map, how to use the radios, how to stay out of airspace they shouldn't be entering.
They understand Mr. Bernoulli's principle.

What still surprises me is the attitude some of them bring to the table.
I always tell new students not to expect to hover until they have about 5 hours of helicopter time in their logbook.

Many airplane pilots hear the words, but you can tell from their attitude they don't believe me.......they think they will be different. They'll be the guy that gets into the helicopter and amazes me with their virtuosity!

NEVER HAPPENS!

The first hour is a frustrating, humbling experience for anyone.....agreed,
  • Rubberducky?


  • Something else that surprises me.
    I ask ALL my students this simple question, and I almost always get an incorrect answer,
    (Even from the experienced fixed-wingers) :
    Why do we land into the wind?

    The most frequent incorrect answer?
    "Because landing into the wind produces more lift."

    Think you know the correct answer? Leave it in the comments.......no charge for entering my contest!
    I'll give you what I consider the correct answer in an update, here, later.

    UPDATE:Well, that didn't take long........
    Jason's answer is the answer I give to my students. In any aircraft, the difference in ground speed landing into the wind vs. downwind is twice the wind speed. For instance, if you land into the wind at 60 knots in a Cessna 150, and your wind speed is 10 knots comin' straight at ya, your ground speed will be 50 knots.
    But land downwind and you have to ADD the wind speed to your airspeed to get groundspeed, so it will be 70 knots.......
    a difference of 20 knots. On an airplane, the wear and tear on tires is reason enough to land into the wind.

    Of course the critical thing is safety. In airplanes, helicopters, automobiles, etc., as speed doubles, crash forces are squared. It just makes sense to be going as slow as you possibly can if there is a chance of a sudden stoppage in your future!

    Purple Tabby.......I don't know if I can make this really clear here, but I'll try.........For me, having learned to fly helicopters first, and then airplanes......crosswind landings were extremely difficult to learn. In the helicopter you do nothing different during a crosswind landing.......in order to maintain your course on final approach, you naturally tilt the rotor into the wind, and the machine takes care of the crosswind problem for you.
    You don't even think about the crosswind.

    In most airplanes, (not all), you bank into the wind to correct for it trying to blow you off your course, and use rudder to keep the nose headed the direction you want the airplane to go.
    For me, it was a VERY unnatural thing to have to do!
    I still hate crosswind landings in airplanes!

    The rotor is also the braking system on the helicopter. Similar to reversing thrust upon landing in an airplane, you just vector the rotor's thrust in the opposite direction of travel, and it provides an effective braking force, (just like birds do when they land!) And similarly to airplanes, if you apply it when you have no forward movement, you can actually go backwards, (except when you do it in the helicopter you are actually flying, not taxiing!)

    Fixed-wingers........is there a way to make this more clear?

    7 comments:

    Jason said...

    My vote is that landing into the wind reduces your groundspeed at touchdown. :)

    Purple Tabby said...

    I agree. Planes have those things on the wings that slow them down before landing but choppers do not (hard to have 'em if there are no wings to hold 'em)
    Also, I believe the "cones" of air displacement can only effect up, down and forward motion. I don't think helicopters have any brakes, so to speak
    This is a WAG though. Do I win something ? :::grin:::

    THIRDWAVEDAVE said...

    Ok, Greybeard, I'll give it a shot. In fixed-wing aircraft, I would say landing into the wind is more about airspeed than anything else. Rotary-wing aircraft, I would imagine, have the same issues at touchdown, as well.

    oleprairiedog said...

    Safety, Safety, Safety. Ask any ole helicopter pilot what happens when hovering or landing downwind and a gust trys to push your nose into the dirt. It gets exciting folks.

    John said...

    This is a late entry, but anyone who has ever done or watched skydiving knows that a downwind landing is to be avoided at all costs because - you can hurt yourself!

    Yet fixed-wing pilots sometimes have to accept a downwind landing and need to know how to handle it. An airport I fly to regularly has only one ILS approach and when the ceiling and visibility are low, a circle to land is not practical. So you shoot the ILS and land with a tailwind.

    Of course, in a helicopter you can do all sorts of things - hover, fly sideways and backward - that you can do in a fixed-wing aircraft only once. ;-)

    Greybeard said...

    I dunno John......
    Seen Sean Tucker's show lately?
    The sideways stuff he does is unbelievable!

    Aviatrix said...

    I'm stunned that pilots wouldn't get the right answer here. I teach girl guides (7-10 year olds) the material for their aviation badge and that's one of the things they have to know.

    The wing-down crosswind landing technique becomes natural if you think in terms of using the rudder pedals to remain aligned with the runway centreline, while banking towards the wind that is trying to push you off it.