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DroopTip
02-20-2008, 01:29 PM
I have been hearing alot of different techniques lately about the best way to climb when enroute climbing to a high altitude (say 10000ft). Ill give an example: transition from takeoff climb to 2500rpm, 1 notch flaps, lean for egt, 75kts indicated all the way up. Id like to hear what other configurations people use during this phase of flight when climbing in a shortwing.

Josh

d.grimm
02-20-2008, 08:48 PM
My personal idea is climb at VY (best rate) in a clean configuration and lean for best power as you climb. I am sure there is a number for VY at different altitudes to take into account the difference between indicated and true.
Something to try at altitude is climb at VX (best angle) and pull the power, simulating a power failure at 500 ft or below.
I think you will find that you are unable to get the nose down to maintain a glide speed that would allow any type of landing flare.
Something to think about next time you need to climb over obstacles. Not saying don't do it, just be aware of the risks.
Dave

Bultaco Jim
02-20-2008, 09:32 PM
I would agree with D. Grimm on a clean configuration. My 22/20 gains 100fpm as soon as I go from half flaps to clean. I seem to get the best rate at 90 mph. Then, I lower the nose for better visability, to 100-105 mph and a still healthy rate for the rest of the climb. I too like to fly high (especially out west). Jim

Stephen
02-20-2008, 11:04 PM
Interesting, I've been watching my VSI when I climb out and to go from 40 degrees to 0 degrees flaps, in my plane it turn out be be less than a 50 fpm decrease. If I keep it on a steady 80 mph. I had some buddies learning to fly in their Tri-Pacer, that were chewed out by their instructor for taking off, using any flaps because it would destroy their climb out.

Hyrdflyr
02-21-2008, 12:29 AM
Typically, flaps get you a better angle of climb, and rate of climb is best without flaps at lower altitudes Varies with weight and airspeed, but most assuredly if you have to get out over the trees, use a notch of flaps, and if they are getting REALLY close, pin the airspeed at VX EXACTLY and hope you don't lose the engine. A pacer with 15-160 hp standard condition sea level will climb at maximum angle of climb with a notch of flaps at a really low INDICATED airspeed at full power if you are at or under gross weight. Density altitude messes that up greatly. A great benefit of tripacer/pacers is that they will tell you what isn't working if you're paying attention. In the end, its what works for your airplane, the way you fly it.. Test it at different altitudes, weights, speeds etc.

If I go really high, ( for a shortwing) say over 8 or 9000 ft, I sometimes pull on a notch of flaps when climbing. One, the airplane will climb better at INDICATED speeds below vy and lower when the air is thinner, and two, it is a lot more solid feeling when you are running out of wing.

I once took a 185 on floats over Denali ( 20,320 ft or so) with three passengers and half fuel. It wanted to quit climbing at about 17 or 18 thousand feet but with a notch of flaps we went by the summit still climbing about a needle's width on the VSI. It was kind of funny when I looked around and found that my passengers had all gone to sleep! I was kinda blue myself.

I do note that in checkouts I love to take the airplane to altitude, and power off, pull on full flaps, full aft elevator, and holding altitude, walking the rudders hard to keep the wings level. When it does stall, It just bobs up and down, stalling and unstalling and indicates about 500 fpm down on the vsi with nothing showing on the airspeed. That's at a forward CG.

It would be gutsy, but I think if I lost it all on a low altitude high angle, climb out, still over the runway, it might pay to pull on full flaps, ease the yoke all the way back, keep the wings level with the rudder and let it go in.

Try it at altitude. I bet you would walk away. I don't think it would work in anything but a tri/or pacer though. I'm not sure why. I've never seen anything approaching 500fpm down in anything else in that mode except a Helio. Maybe a Stinson would do it. More like 7-800fpm in most Cessnas etc. Must be the short wings huh? :lol:

DougG
02-27-2008, 10:03 AM
HI, I've done a fair bit of mountian flying while doing geophysical surveying. This involves flying up and down the sides of mountains breaking just about every rule you will ever hear concerning mountian flying. One job was testing the limits of the airplane with altitudes of 23,000ft. In this airplane, a Caravan, best climb rate is clean with no flap, as your altitude increases the indicated airspeed will deacrease until you reach or are near the service ceiling when it will be the same as best angle of climb speed. Having flown Single Otters that like a little flap to climb I experimented with various flap setting to improve on this but it, and I think 99% of all airplanes, always climb better clean.
I can't remeber the service ceiling of the Pacer but I've had my 125 hp Pacer up to 12-13,000 ft a few times to try and catch a good tail wind. It has to be a really good wind to make it worthwhile going over about 9,000ft because you lose so much power from the engine at these altitudes. One trick to get a few more feet when the airplane doesn't want to climb any more is to fly straight and level until you reach the max indicated speed it will do and then raise the nose slowly and climb until the speed drops to best rate and hold it there. When the VSI starts settling toward zero lower the nose without losing altitude and let the airspeed build again. When your max indicated airspeed is down to best rate of climb speed you are about as high as you are going to go.
Doug

DroopTip
02-27-2008, 06:07 PM
Thanks for the replies guys, some different opinions on these climbs was exactly what i was looking for! DougG, i really like the bobbing for altitude method. Reminds me of driving my 1500cc honda civic on the interstate at 65, getting up to about 80 befor a big hill so not everyone and there brother had passed me by the time i got to the top. 8-) I figure if i get pulled over for speeding befor i hit the hill ill just tell the cop that by the time i hit the top my average speed will still be less than 65. Anythings worth a try. ;)

josh

Bultaco Jim
02-27-2008, 11:04 PM
This has been nagging me for a week now. Several posts back, Hyrdflyr talked about the plane mushing through the air at about 500fpm down, with full back elevator, as a possible alternative landing configuration. I, too, had fantasized along those lines after putting VG's on the Colt (it won't stall anymore). I was thinking of using this for an engine-out over really bad country. The reason I'm posting now, is, I recently read that the human body can take a frontal force,(like in a car or plane crash) that's 5 times more than a vertical force, (like jumping off a building feet first). I now believe that you should fly the plane all the way to the full stall,just like we were all taught, and not "sit down" on impact, for physical reasons. I figured if two of us had contemplated this type of landing, there might be more! Jim

Hyrdflyr
02-28-2008, 03:06 AM
Back to the 500 fpm vertical descent: :D

If I lose the engine at night over "bad" terrain and hold a steady 60 mph descent rate until the crash (Touchdown seems too optomistic), I have a forward speed of 88 feet per second. Hmm,

At 500fpm descent stalled out, 500 divided by 60 seconds is 8.33 feet per second descent rate.

Still sounds better to me. I think I've landed harder than that a time or two already.
( I rode bucking horses for some time while younger and I'm sure I've exceeded 500 fpm on occasion when coming off in uncontrolled flight, as it were.) Sometimes seems like just yesterday when I get up in the morning. :cry:

Steve Pierce
02-28-2008, 07:37 AM
Steve Johnson was giving Cathy some instruction in our Pacer last week. They couldn't get it to stall, just kinda mushed.

I fell straight down from 80-100 feet in my Clipper. The airplane was stuck in the ground like a lawn dart and I am here to tell about it. :shock: Our little airplanes are very crash worthy in my opinion.

I remember leaving Rock Springs, Wyoming headed east and not being able to climb until I would get under a cloud. As soon as I cleared a cloud I was back to straight and level flight. :lol:

Jim
02-28-2008, 08:00 AM
Hi,

........I have a forward speed of 88 feet per second. Hmm,

........At 500fpm descent stalled out, 500 divided by 60 seconds is 8.33 feet per second descent rate.

I think it's not one or the other here, you always have both components to deal with. Your 500 feet per minute fall would only be correct in a vertical fall.

taildraggerpilot
02-28-2008, 08:03 AM
Back to the 500 fpm vertical descent: :D

If I lose the engine at night over "bad" terrain and hold a steady 60 mph descent rate until the crash (Touchdown seems too optomistic), I have a forward speed of 88 feet per second. Hmm,

At 500fpm descent stalled out, 500 divided by 60 seconds is 8.33 feet per second descent rate.

Still sounds better to me. I think I've landed harder than that a time or two already.
( I rode bucking horses for some time while younger and I'm sure I've exceeded 500 fpm on occasion when coming off in uncontrolled flight, as it were.) Sometimes seems like just yesterday when I get up in the morning. :cry:

Just a slight correction, when your descent rate at stall is 500 fpm, you still have a forward component of velocity. Assuming your stall speed is 50 mi/hr coupled with a vertical descent of 500 ft/min, you will still impact the ground at 73.5 ft/s.

Bultaco Jim
02-28-2008, 11:07 AM
I can't help thinking about all the pilots who have never flown one of our planes, especially CFI's, being blown away by this whole conversation. They'd still be asking-"waddayamean it doesn't stall?!"

Hyrdflyr
02-28-2008, 09:20 PM
"Just a slight correction, when your descent rate at stall is 500 fpm, you still have a forward component of velocity. Assuming your stall speed is 50 mi/hr coupled with a vertical descent of 500 ft/min, you will still impact the ground at 73.5 ft/s."

I think that you are correct if you hit the ground just as the airplane stalls or shortly after.

However, having held the airplane in a fully stalled out , nose bobbing condition for some time, (about a full minute at different times while teaching students to "walk the rudders to keep the wings level", I am convinced that the forward airspeed deteriorates very quickly and would be essentially nil after a short time, since the drag of a fully stalled airplane is tremendous relative to forward flight.
Remember, this is power off.

I believe that is why the altitude needed to recover flying speed is so great when recovering from a deep stall break in most aircraft.( think spam can).

The airplane has lost its forward momentum and must dive to regain sufficient airspeed for the wing to "fly" again.

In this case, I will take my partner with me this weekend to keep me honest and see what the forward airspeed is in the fully stalled state according to Mr. Garmin. Actually, I have had the GPS on the panel through several of these exercises, just never noticed what it indicated!

Will report back, good or bad.

Caveat: My beliefs are my own and I don't recommend that anyone attempt this without taking full personal responsibility for their own actions. I wouldn't try it in anything but a Pa 22/20 under certain conditions.

"I can't help thinking about all the pilots who have never flown one of our planes, especially CFI's, being blown away by this whole conversation. They'd still be asking-"waddayamean it doesn't stall?!"

Just tell them that it doesn't glide for xxxt, but sure stalls nice!!