PA28 180 Take off
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PA28 180 Take off
Hey all, New to the site, I just bought a PA28 180. The POH says Vr 55-60 and "let the plane fly itself off". Well it don't work that way with me. The first time I tried it, stall light on, plane wallows like a pig with 4 foot wings and it mushed down. Now I get up to 70 knots get it off the ground and release some back pressure, Works ok, but I wonder way I need so much speed over the POH recommendation. Perhaps the 5200 ft altitude? Anybody got experience with this...Thanks a lot...jerry
The airport elevation does not effect the Vr as an Indicated Airspeed although the True Airspeed will be higher, hence longer take off roll etc.
I am not too struck on the idea of "Vr" in a light aircraft - it's more a question of accelerating to the correct speed and then selecting the take off attitude and then waiting for the machine to fly itself off the ground. Don't expect to immediately get airborne when you select the take off attitude!
Also where have you set the trim for take off - might be worth experimenting a little with this.
However, my best suggestion is to find a good instructor who is experienced on the type and take some training from him/her.
Hope this helps
I am not too struck on the idea of "Vr" in a light aircraft - it's more a question of accelerating to the correct speed and then selecting the take off attitude and then waiting for the machine to fly itself off the ground. Don't expect to immediately get airborne when you select the take off attitude!
Also where have you set the trim for take off - might be worth experimenting a little with this.
However, my best suggestion is to find a good instructor who is experienced on the type and take some training from him/her.
Hope this helps
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PA28-180 Take Off.
Jerry,
I note your address as AZ (Arizona) does temperature, and density altitude come to mind??
Go find a competant instructor and go over the numbers.
I also agree that light aircraft Vr numbers are not really any use. The airplane, or rather the wing, has an angle of attack that will give you the performance you require. Therefore find the correct attitude and it will fly itself off.
I had one for several years, a great airplane.
Brian
I note your address as AZ (Arizona) does temperature, and density altitude come to mind??
Go find a competant instructor and go over the numbers.
I also agree that light aircraft Vr numbers are not really any use. The airplane, or rather the wing, has an angle of attack that will give you the performance you require. Therefore find the correct attitude and it will fly itself off.
I had one for several years, a great airplane.
Brian
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pa28 180
Thanks a lot guys, this is a great site, I love this plane and I really enjoy geting up early before work and practicing in the pattern and slow flight etc. The 70 ish speed has been working so I think I will stay with that, seems comfortable and more respondsive after the wheels lift off the ground. Flys sweet. One more question , if I may trouble you guys again. I approach at 80 kts. Many on this site are saying closer to 70-75. I am used to a cessna at 60-65, full flaps. I would like for it not to float so much. Any suggestions.?? thanks again....what a great site!!
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Approach
Hi JerryB12
Try approach at 75kts until last mile / 300 ft alt, then lower last stage of flap should bring you back to 70 without power change then at VAT reduce speed to 65 kts providing you lift the nose / flare, should be a sweet landing.
Carbon
Try approach at 75kts until last mile / 300 ft alt, then lower last stage of flap should bring you back to 70 without power change then at VAT reduce speed to 65 kts providing you lift the nose / flare, should be a sweet landing.
Carbon
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Pa28-180
Jerry,
Please don't think me harsh, but you are showing a general lack of experience, and my earlier suggestion to go and fly with a "qualified" (as in experienced PA28-180) instructor means more with each post. The airplane is a nice easy machine to fly, but you will aways fly better after good instruction.
The airplane should approach at 1.2 or 1.3 times the stall speed with suitable adjustments for wind gusts etc. 80Kt. is rather high and I would expect you float quite a bit? That manual was written by good experienced people with good reason.
Have you stalled the machine yet?? Make sure your instructor shows you. It is very docile.
Please remember that a good approach will give a good landing. Correct approach speed equals a good landing speed!
Where you appear to be from needs a healthy respect, and understanding of density altitude. Please get some advice.
Brian.
Please don't think me harsh, but you are showing a general lack of experience, and my earlier suggestion to go and fly with a "qualified" (as in experienced PA28-180) instructor means more with each post. The airplane is a nice easy machine to fly, but you will aways fly better after good instruction.
The airplane should approach at 1.2 or 1.3 times the stall speed with suitable adjustments for wind gusts etc. 80Kt. is rather high and I would expect you float quite a bit? That manual was written by good experienced people with good reason.
Have you stalled the machine yet?? Make sure your instructor shows you. It is very docile.
Please remember that a good approach will give a good landing. Correct approach speed equals a good landing speed!
Where you appear to be from needs a healthy respect, and understanding of density altitude. Please get some advice.
Brian.
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Yup i always approach at 75 Kts no faster with two stages of flap threw in, + on the takeoff rotate at around 65kts beforehand adding sum slight backpressure to ease load on the nosewheel she usually lifts off nice.
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I rotate and climb at 80mph, approach at 80mph. However I do have lots of runway to play with. Flies almost exactly the same as our Cherokee 140 does, as you'd expect. Nice machine, but a bit old.
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Perhaps the 5200 ft altitude?
Your pitch attitude at Vy when climbing out is going to be a lot shallower than what you might be used to at Vy in the lower lands.
One of the gotchas of flying in the mountains, there aren't many, but you just found one. Reach Vr, pull back, pitch for the attitude you are used to at 100ft MSL, stall, crash.
Get somebody who knows about mountain flying to teach you what to do. You might just kill yourself if you don't. Remember that at the shallower angle of climb you need to clear that mountain off the departure end, so feet per mile is what you should be thinking. Not feet per minute.
When landing fly the normal IAS numbers, but expect to spend more time on the runway before you can pull off. That's because your TAS is higher, you should know that, so go learn it. The gotcha is that you spend so much time on the runway that you run off the end. Don't cross the fence at 80kts, cross it at what the book says, should be around 65 in an archer.
Two mountain flying gotchas in one post. Not bad at all....
Last edited by slim_slag; 23rd Jul 2007 at 17:51.
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Did you consider that at 5200 feet the engine is receiving approximately 25 inches of manifold pressurem versus approximately 30 inches at Sea Level ? - That's a LARGE reduction in power, and accounts for the lower pitch attitude necessary at the higher altitude.
Going back to the original post (the reports of the aircraft "mushing: back onto the ground), if your rotation rate and attitude is the same as at sea level, with the MUCH reduced power, I'm not surprised at all. Gentler rotation to a lower pitch attitude is the name of the game
Regards,
Old Smokey
Going back to the original post (the reports of the aircraft "mushing: back onto the ground), if your rotation rate and attitude is the same as at sea level, with the MUCH reduced power, I'm not surprised at all. Gentler rotation to a lower pitch attitude is the name of the game
Regards,
Old Smokey
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I had a Cherokee 140 and used to fly a rental 140 regularly. The rental would do as the book says, and would fly off more or less on its own with gentle back pressure at book speed. On the other hand, mine fairly had to be yanked off with a strong pull of the yoke, and it would stagger into the air and need some time in ground effect to regain its composure (my current ride, my Beech Sundowner, fairly leaps into the air when you rotate at 65 knots, no matter what the load).
One thing to check on Cherokees as a contributing factor: the pressure in the main and nose gear oleos. Some tend to sit low on their main gear with a nose-high attitude, some have a nice perky stance if the oleos are properly inflated. Sitting nose-high will give a higher angle of attack, and this will signficantly affect behaviour at rotation, more than likely even more serious at high density altitude.
One thing to check on Cherokees as a contributing factor: the pressure in the main and nose gear oleos. Some tend to sit low on their main gear with a nose-high attitude, some have a nice perky stance if the oleos are properly inflated. Sitting nose-high will give a higher angle of attack, and this will signficantly affect behaviour at rotation, more than likely even more serious at high density altitude.
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Did you consider that at 5200 feet the engine is receiving approximately 25 inches of manifold pressurem versus approximately 30 inches at Sea Level ? - That's a LARGE reduction in power, and accounts for the lower pitch attitude necessary at the higher altitude.
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I would seriously go and do some circuits with an instructor.
However, I teach to 'rotate' if you like at 65knots. By this I mean apply positive back pressure to lift the aircraft off the runway in order to set a climbing attitude. This 'attitude' is where the nose of the aircraft partially obscures the horizon. When established in the climb with this 'climbing attitude' trim the aircraft. Without even looking at the ASI this will give you a best rate of climb speed of 75knots.
Approach
I would be careful configuring the aircraft 300ft above the ground.
Concentration should be on flying the correct flight path and at the correct speed, not configuring the aircraft so close to the ground. What if you get assymetric flap deployment? Can you handle that 300ft above the ground? What if you inadvertently balloon? You then have an upset to your flight path coming into land. Great if you have a 13000ft runway but maybe not on a 500m grass strip.
Does the checklist tell you, you can lean the mixture for take off? Does the POH tell you to lean the mixture for take off? By how much and for how long? Doesn't fuel have a cooling effect?
When hot and high in a normally aspirated engine, your performance is gonna be pretty reduced. You therefore have to watch your airspeed and give your engine plenty of TLC !!
If you have doubts its got to be worth having an hour with an instructor ??
However, I teach to 'rotate' if you like at 65knots. By this I mean apply positive back pressure to lift the aircraft off the runway in order to set a climbing attitude. This 'attitude' is where the nose of the aircraft partially obscures the horizon. When established in the climb with this 'climbing attitude' trim the aircraft. Without even looking at the ASI this will give you a best rate of climb speed of 75knots.
Approach
Try approach at 75kts until last mile / 300 ft alt, then lower last stage of flap
Concentration should be on flying the correct flight path and at the correct speed, not configuring the aircraft so close to the ground. What if you get assymetric flap deployment? Can you handle that 300ft above the ground? What if you inadvertently balloon? You then have an upset to your flight path coming into land. Great if you have a 13000ft runway but maybe not on a 500m grass strip.
Also, are you leaning the mixture for takeoff?
When hot and high in a normally aspirated engine, your performance is gonna be pretty reduced. You therefore have to watch your airspeed and give your engine plenty of TLC !!
If you have doubts its got to be worth having an hour with an instructor ??
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Does the checklist tell you, you can lean the mixture for take off? Does the POH tell you to lean the mixture for take off? By how much and for how long? Doesn't fuel have a cooling effect?
Back in the 70s when I was flying 172s, 177RGs, and 310s in Puerto Rico on 115/145 AvGas, we leaned for takeoff even at sea level (normally hot & humid -- high density altitude). Without leaning, plug fouling was atrocious! Only the 177RG had any problems with high CHT on climb...
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I should reinforce the comments about correct approach speed. My home field is 5000 ft long, 400' ASL. The rented plane's instructor insisted that I approach at 85 mph...yes, 85 mph. That was WAY too fast and the float was atrocious. The book said, if memory serves, 85 with NO FLAPS, then 82 first notch, 79 second notch, and 76 full flaps. Well when I flew solo I soon tossed aside my instructor's instructions and flew it by the book (as I did my own Cherokee when I had it), maybe adding a couple of mph for gusty conditions. Landings and landing distances improved remarkably.
In my current bird, approach is 80 knots (92 mph) flapless and first notch, then 75 knots second notch, and 68 knots full flaps. The Sundowner is notorious for being a "fly by the numbers" type on approach. Those who don't have gotten gotten into some pretty nasty porpoising and wheelbarrowing situations. Even 75 with two notches is too fast I find; I slow it back to 70 just over the fence; full flaps, I use 70 knots max.
Today was an interesting situation, nice day, about 22C when I was flying, light and variable crosswind. The Sundowner likes to land with the stall warning honker blaring away; you flare, hold it off, and when the honker starts honking, pull full back on the stick and plonk it on; do this and a smooth touchdown is almost guaranteed. I came over the fence in a variable crosswind. The first clue was some windshear on final that caused me to suddenly pick up 10 knots of airspeed, which I bled off before crossing the boundary. Then on landing, the stall warning honker started blaring, and I made what I thought was a nice, normal and fairly smooth landing, but the wind shifted again, and the plane literally bounded back up into the air; I was low, slow and in ground effect. Instinct would have been to shove the nose down and try to force it back on. I have a friend who did that with a Sierra (retractable gear version of my plane) and promptly took off the nosewheel and bent the prop. I kept it in ground effect, applied full power, got the speed back up, and did a go-around, which I believe was the right thing to do.
I made sure I landed right on the book speed the second time around. I was a knot or two fast on the first attempt, and I did a two-notch landing as the taxiway was at the departure end of the runway, so no need to come in short. I used full flap the second time, speed smack on 68 knots.
While the Sundowner flies differently than the Cherokee, my point is that the book was written after hours and hours of flight testing. When all else fails, read the instructions! Some planes will forgive fudging approach speed on the high side (assuming you're not on a performance limiting field), but others, like mine, thrive on precision. At the end of the day, even if your plane will accept fudging like the good ol' forgiving Cherokee, it will reward you if you fly it with precision.
Beech
In my current bird, approach is 80 knots (92 mph) flapless and first notch, then 75 knots second notch, and 68 knots full flaps. The Sundowner is notorious for being a "fly by the numbers" type on approach. Those who don't have gotten gotten into some pretty nasty porpoising and wheelbarrowing situations. Even 75 with two notches is too fast I find; I slow it back to 70 just over the fence; full flaps, I use 70 knots max.
Today was an interesting situation, nice day, about 22C when I was flying, light and variable crosswind. The Sundowner likes to land with the stall warning honker blaring away; you flare, hold it off, and when the honker starts honking, pull full back on the stick and plonk it on; do this and a smooth touchdown is almost guaranteed. I came over the fence in a variable crosswind. The first clue was some windshear on final that caused me to suddenly pick up 10 knots of airspeed, which I bled off before crossing the boundary. Then on landing, the stall warning honker started blaring, and I made what I thought was a nice, normal and fairly smooth landing, but the wind shifted again, and the plane literally bounded back up into the air; I was low, slow and in ground effect. Instinct would have been to shove the nose down and try to force it back on. I have a friend who did that with a Sierra (retractable gear version of my plane) and promptly took off the nosewheel and bent the prop. I kept it in ground effect, applied full power, got the speed back up, and did a go-around, which I believe was the right thing to do.
I made sure I landed right on the book speed the second time around. I was a knot or two fast on the first attempt, and I did a two-notch landing as the taxiway was at the departure end of the runway, so no need to come in short. I used full flap the second time, speed smack on 68 knots.
While the Sundowner flies differently than the Cherokee, my point is that the book was written after hours and hours of flight testing. When all else fails, read the instructions! Some planes will forgive fudging approach speed on the high side (assuming you're not on a performance limiting field), but others, like mine, thrive on precision. At the end of the day, even if your plane will accept fudging like the good ol' forgiving Cherokee, it will reward you if you fly it with precision.
Beech