Landing with max weight capacity

odachoo

odachoo

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Odachoo
Today I was in a situation that I took off with max allowed weight based on the WAB sheet. It's a 172N with 860 useful load and I was right on 850 pounds when I did my WAB calculations.
Taking off was fine, smooth climb and nothing out of norm there.
When it comes to landing, it was very different compare when the plane is light. My landing was bouncy, even I was right on 60knts air speed on short final. Wind was calm too. I can't think of anything wrong or what I should have done to make a smooth landing !

My question is that what should be considered when the plane is heavy and what should be done for smooth landings when plane is in full weight.

Thanks,
-Patrick
 
The stall speed is higher with heavy weight, so the approach speed should be as well.

60 KIAS works nicely at 2000 lbs, but at 2300, 65 may make more sense.
 
If you bounced, then you had too high a vertical speed, and possibly too much energy if you didn't have to add power to cushion the bounce recovery.

Always a good idea to practice flying at the different places on the CG envelope at various weights. Many flight schools I know have sandbags that can be added to the plane to move the CG and adjust the weight. Try this with an experienced CFI sometime, it's an eye-opening experience.
 
odachoo said:
Today I was in a situation that I took off with max allowed weight based on the WAB sheet. It's a 172N with 860 useful load and I was right on 850 pounds when I did my WAB calculations.
Taking off was fine, smooth climb and nothing out of norm there.
When it comes to landing, it was very different compare when the plane is light. My landing was bouncy, even I was right on 60knts air speed on short final. Wind was calm too. I can't think of anything wrong or what I should have done to make a smooth landing !

My question is that what should be considered when the plane is heavy and what should be done for smooth landings when plane is in full weight.

Thanks,
-Patrick
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I'll bet the difference in feel wasn't as much due to the extra weight as it was to a more aft CG than you are used to. As the CG moves aft pitch control get lighter and more sensitive which in turn leads to overcontrolling. The "fix" is to pay close attention to attitude and sink rate as you round out. If you've got the nose up enough to land on the mains and your sink rate is adequately low there won't be any bouncing in a 172.

As to the notion you needed more airspeed I'd say that's generally not a good idea. 1.3 * Vso is just under 60 KIAS at max weight so that's about as fast as I'd be comfortable with "over the fence". What you might want to do is reduce your speed at lighter weights to get a better feel for what a max weight landing ought to be like. That said the variation in speed for 2200 vs 2400 lbs isn't more than 2.5 Kt and that's not hardly enough to worry about.
 
gismo said:
I'll bet the difference in feel wasn't as much due to the extra weight as it was to a more aft CG than you are used to. As the CG moves aft pitch control get lighter and more sensitive which in turn leads to overcontrolling. The "fix" is to pay close attention to attitude and sink rate as you round out. If you've got the nose up enough to land on the mains and your sink rate is adequately low there won't be any bouncing in a 172.

As to the notion you needed more airspeed I'd say that's generally not a good idea. 1.3 * Vso is just under 60 KIAS at max weight so that's about as fast as I'd be comfortable with "over the fence". What you might want to do is reduce your speed at lighter weights to get a better feel for what a max weight landing ought to be like. That said the variation in speed for 2200 vs 2400 lbs isn't more than 2.5 Kt and that's not hardly enough to worry about.
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:yeahthat:
Even at below max GW, but with 2 in the back seat and a light weight pilot will move the CG aft, and still within limits. It's not just the weight, it's the CG shift to what you are not used to. Aft CG, more pitch sensitive.
 
BillTIZ said:
:yeahthat:
Even at below max GW, but with 2 in the back seat and a light weight pilot will move the CG aft, and still within limits. It's not just the weight, it's the CG shift to what you are not used to. Aft CG, more pitch sensitive.
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That make perfect sense. How can I practice that ? put sand bags on back seats ?
 
How did it bounce? Flare high and drop in? Not enough flare and hit hard on mains? Nosewheel first and wheelbarrow?
 
wabower said:
How did it bounce? Flare high and drop in? Not enough flare and hit hard on mains? Nosewheel first and wheelbarrow?
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I flared at the normal height, the ground effect didn't hold the plane there since we were heavier I guess.
 
Dave Krall CFII said:
I like people that want free airplane rides, great GA PR.
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Not sure practicing landings with a weird weight/CG combo that produces 'bounced landings' is the great PR GA needs...:confused:

I do agree people would be ideal over sand and water though.
 
Captain said:
Not sure practicing landings with a weird weight/CG combo that produces 'bounced landings' is the great PR GA needs...:confused:

I do agree people would be ideal over sand and water though.
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Include rum & cokes for passengers getting free airplane rides. Great PR! :lol:
 
Geico266 said:
Include rum & cokes for passengers getting free airplane rides. Great PR! :lol:
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Well he didn't say THAT!! If that's the case then I'll be happy to ballast the back seat!

:)
 
My Cessna 180 has 96 gal tanks and the cheap self-serv is 40 miles away and directly on the way to our farm. As a result I often tanker a full load of fuel on the return trip and am pretty close to max gross for landing if anybody else is riding along.

I've learned to add just a little power during flare when it's heavy. No appreciable approach-speed change is necessary, since I'm slowing to flare anyway, but a 100-200 rpm will help soften the descent ever-so-slightly by allowing you to put the tail where you want it and keep it there while the plane gradually sinks onto the runway. If you add too much power it will just fly along until you reduce it slightly.

Flying the length of the runway in landing configuration with just enough power to remain airborne is a great drill for any pilot, so you might try it the next time you fly in order to help develop the feel for those last few feet of descent. After a couple of passes down the runway (find a long one if you can) you'll have a much better idea about how your plane performs as well as a better sense of the power required.



odachoo said:
I flared at the normal height, the ground effect didn't hold the plane there since we were heavier I guess.
Click to expand...
 
+1 for adding just a touch of power right before the flare, especially when heavy. Unless you are doing short field ops it will also help you land smoother at normal weights. Just enough to hear the change in the engine.

Doesn't help in all planes but does in the 172. Just remember to pull the power back out after the nose wheel touches down.


Sent from my iPad using Tapatalk HD
 
Just go fly. Find some friends to go with you if you are worried about practicing with heavier weights. I wouldn't worry too much about it
 
ZG_Mooney said:
+1 for adding just a touch of power right before the flare, especially when heavy. Unless you are doing short field ops it will also help you land smoother at normal weights. Just enough to hear the change in the engine.

Doesn't help in all planes but does in the 172. Just remember to pull the power back out after the nose wheel touches down.


Sent from my iPad using Tapatalk HD
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It is NOT necessary to leave power on let alone add power in the flare to get a decent landing. Unless you've come into the roundout too slow for the vertical speed you're carrying (e.g. pulling the nose up slightly in an early anticipation of the touchdown). What power does in the flare is stretch the time from start of roundout to touchdown and that CAN make it easier to achieve a smooth touchdown at the expense of increased landing distance.

In any case I'd say if you do carry power though the flare, you should at least remove it as soon as the mains are rolling on the ground which should occur long before the NOSE wheel touches down.
 
Captain said:
Not sure practicing landings with a weird weight/CG combo that produces 'bounced landings' is the great PR GA needs...:confused:

I do agree people would be ideal over sand and water though.
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It's never been a problem so far, and no refunds have been given.
 
We're talking about a ~200 RPM for maybe 10-15 seconds at most to smooth the touch-down.
gismo said:
It is NOT necessary to leave power on let alone add power in the flare to get a decent landing. Unless you've come into the roundout too slow for the vertical speed you're carrying (e.g. pulling the nose up slightly in an early anticipation of the touchdown). What power does in the flare is stretch the time from start of roundout to touchdown and that CAN make it easier to achieve a smooth touchdown at the expense of increased landing distance.

In any case I'd say if you do carry power though the flare, you should at least remove it as soon as the mains are rolling on the ground which should occur long before the NOSE wheel touches down.
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