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Bill, You're right in almost every particular. Except, the flight and landing characteristics of the D aren't Draconian at all. Indeed, my Coupe was correctly rigged with 9° up travel as carefully confirmed at the elevator while the yoke was being held full back. Remember that the only change is in the LIMIT of the up travel. The only time you reach that limit is at the END of the flare or in a particular emergency I'll discuss below. During an approach, you should be flying at about 30% above minimum flying speed. This gives a fine cushion of energy to be used for the flare. I normally flew my approaches with 1500 rpm and reduced power to idle somewhere along final when I was sure I had the field guaranteed. I liked to fly down the last part of final (at 130% minimum flying speed) at IDLE power to ensure that no power loss could spoil my day. In case power failed on downwind or base, I practiced making an immediate turn to the runway. In case power failed right at the turn to final, I could have a problem if I was aiming at the numbers on a SHORT field but the 30% extra energy might have gotten me to the threshold. Once I got to my guaranteed "make it" point, I pulled back power to idle. If I misjudged high on a short airport, I'd just sing a bar of Ken Dravis' song "You can always go around" and I'd go around. I treated every landing as practice to optimize my judgment and didn't have to go around much at all. Now the minimum flying speed on the D should be about 5 mph faster than minimum flying speed on the C. Yet with each, you should have that 30% extra speed coming down the approach and that energy converts into a fine flare and touchdown. In the last few seconds of flight, the difference in elevator up travel comes into effect as the C gets a little bit more up travel and 5 mph lower touchdown speed. The difference in speed IS important if you subsequently run into something because you're doing it with more energy. The people used to landing at the slower speed often didn't like having to land faster and a better solution was sought. Pilots who get out of a C and fly the approach in the D at the same speeds they are used to, have lost a big percentage of the energy they should have for reserve and flare. My rule of thumb in ANY Coupe is to go to altitude on the first flight and determine the minimum flying speed for THAT aircraft with THAT airspeed indicator. Then I fly the approach at 130% of the indicated minimum flying speed of THAT plane. Bill wrote: > My recollection is that nose-high trim in the "D" > with power gave the most benign descent and arrival. > Loss of power on such an approach, once committed, > would result in a touchdown both earlier and shorter > than desired...before the runway and maybe into the > "blast" fence. The fence at the other end of the > runway was certainly not a factor of concern! Bill, if you're flying your approaches nose high with power, you're at risk and you're right that the difference between C and D up-elevator travel might make a difference. Ain't gonna catch me doing that! (See discussion above.) If a pilot in a Coupe gets low and too slow and is heading downhill near the ground with no spare airspeed to convert to a nice flare, the difference between C and D is critical. In this case, the C can (maybe) pull full up-elevator and get the plane to flatten out before impact and land flat where a D pilot might not have enough elevator and hit nose-gear first. I'd sure recommend that NO Coupe pilot get him/herself into such a stupid situation. Yeah, you can drag it in to landing under power at low airspeed but you've got to be VERY aware that a wind shear, negative gust, or loss of power will leave you in probable crash mode. The difference between C and D up travel might make an important difference in that situation but the POOR JUDGEMENT of the pilot is the real cause of the crash. Ed Burkhead http://edburkhead.com/ [EMAIL PROTECTED] (remove the XXX) -----Original Message----- From: William R. Bayne [mailto:[EMAIL PROTECTED] Sent: Saturday, September 06, 2003 12:38 AM To: COUPERS - TECH Subject: Re: [COUPERS-TECH] glide ratio - Clarification to 9/4/03 11:12post ----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]---- Yo, Ed Are you sure the "D" you made these hundreds of landings in was rigged, per Type Certificate 787, for 9º max. up elevator (the rudder hole is at 13º for the "C")? Are you sure the control shaft had its stop located per spec.? Are you saying that four degrees difference in up elevator movement don't significantly affect landing characteristics? Fred Weick was so disappointed in the landing characteristics of the spec-rigged "D" Model (as CAA approved) that only two production ones left the factory. I understand the original owners of both had these ships converted to Model CD (with 13º up elevator, but only 1260# gross allowed) as was all subsequent factory production until Sanders' "E" Model. My recollection is that nose-high trim in the "D" with power gave the most benign descent and arrival. Loss of power on such an approach, once committed, would result in a touchdown both earlier and shorter than desired...before the runway and maybe into the "blast" fence. The fence at the other end of the runway was certainly not a factor of concern! Any coupe with the split elevator becomes an "E" Model or higher They aren't rigged as a "D" nor do they fly like one. The sole reason the split elevator came to be was to regain the authority lost with the 9º limit, secure the CAA's blessing, and achieve a usable 1400# gross weight (a huge selling point over earlier models). BUT does anyone that has flown a "C" or "CD" much really like the change in yoke "feel" as the "low speed warning cushion" spring takes effect (or it's weight)? :<) Regards, WRB ---------------------------------------- on 09/05/03 10:56 PM, Ed Burkhead at [EMAIL PROTECTED] wrote: > ----[Please read http://ercoupers.com/disclaimer.htm before following any > advice in this forum.]---- > > > > Bill wrote: >>> > The "D" Model does not have the up-elevator authority to > bleed off forward speedthis way...it doesn't land well > without full "noew-up" trim...which means if you lose > power late in your usual approach you land short with > forward progress possibly arrested by the wrong side of > the airport fence! The 9º up elevator limit on the "D" > is a safety hazard created and perpetuated unnecessarily > without meaningful purpose by CAA/FAA bureaucrats! > << > > Bill, > > Rude noise and disagreement. I did many hundreds of landings in a D > without any problems. > > I didn't have to use full nose up trim (even a little old lady can pull > the yoke full back in a Coupe - I just used two fingers to overcome the > trim for the flare). I did in fact bleed off forward speed by gradually > pulling back on the yoke during the flare (6" above the runway) to reach > the limiting stop just as I touched. > > If you lose power late in the approach in a D model, you just keep your > airspeed pegged where you wanted it and do your flare a bit closer to > the end of the runway than you had planned. Since a D should no more be > flown down the final approach at full up elevator than a C should be, it > just doesn't make a darn bit of difference which model you have for this > purpose. > > The only time I was threatened by the fence at the far end of the runway > was when the [EMAIL PROTECTED] Goodyear brakes popped a clip as I tried to > stop at > midfield for the turnoff. Even then, I did a U turn at the end of the > runway and stopped in the weeds without damage. > > I would assert that ANYONE can learn to fly a D model with full safety. > At the same time, I think the FAA should grant a blanket STC for > installing the split elevator on any Coupe that doesn't already have > one. > > Ed Burkhead > http://edburkhead.com/ > [EMAIL PROTECTED] (remove the XXX) > ======================================================================== ====== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/ ========================================================================== ==== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/
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