Too fast on final.

[Rookie50]

You do see it again and again. Certainly I've been guilty, until I figured out my 182 is happiest, uses less runway and sweet touchdowns when I slowed it down to 172 speeds on short final, with just a touch of power. Surprising as it is a big jump in weight from a 172, but that's how good that wing is. Maybe the last owner used special polish. Light, I would think it would have no problem at 55 kias.

Anyway it is a common problem, which leads to lousy landings and makes short fields scary.

Today I was at the hangar, regretfully not flying myself, and watched a fellow -- likely a solo student, again and again come in way too high and fast in a 172, using at least half of our relatively modest runway on touch and goes before touchdown. A bit dicy, to be sure. Tons of float, which a 172 R will happily do forever.

I think the problem partly is speed control, but partly also is, where exactly one is looking on short final. I think at times, my eyes are on the numbers or beyond, so naturally the airplane follows, and over the numbers one then is still 20 feet in the air. When I focus my eyes tightly on the dirt area -- snow now -- right Before the threshold, and refuse to let the nose rise above that point -- at my Vref speed, flare happens right on the numbers, boom, slow, very short minimal energy touchdown.

I should add we're talking your typical Vfr circuit, which means to me a one mile final (or less). A much shallower ILS, aiming at a point just prior to the runway might not work out so well.

[Colonel Sanders]

Congratulations! You are now officially
a Grumpy Old Guy (tm)



You are now authorized to begin every
paragraph with "I remember when ..."

[Rookie50]

I used to ocassionally switch from flyng a 172 RG, which dirty power off sinks fairly readily, which meant you could scream in pretty fast rIght to the circuit area before putting all that drag out, to a 172S, which will glide almost from cruising altitude right to the runway. Power is not your friend in that plane when landing, almost like a DA 20.

[SAR_YQQ]

Airspeed control on final is paramount. Your POH will stipulate an ideal threshold speed for weight category.

Glide slope is maintained by visually maintaining a fixed point on the runway (ie aimpoint) in your windscreen.

Adjust everything else to maintain those two criteria.

If your aimpoint is the runway under-run (ie dirt before where threshold begins) - that is where you airplane is going to land.

Once across the threshold - shift your eyes down the runway - use your peripheral vision to assess the ground rush - don't forget the ever-so forgotten flare.

[Big Pistons Forever]

One big problem in flight training is that flight schools tell students to fly an arbitrary and invariably too fast finals speed for every approach. This is especially a problem with the C 172. With 2 up and half tanks, which is a typical training weight, anything more than 60 kts is too fast.

[Rookie50]

Airspeed control on final is paramount. Your POH will stipulate an ideal threshold speed for weight category.

Glide slope is maintained by visually maintaining a fixed point on the runway (ie aimpoint) in your windscreen.

Adjust everything else to maintain those two criteria.

If your aimpoint is the runway under-run (ie dirt before where threshold begins) - that is where you airplane is going to land.
i].

I find aiming there, then I shift my eyes down runway during the round out, results in the actual flare right over the numbers. Aim at the numbers, round out begins there, flare and touchdown are too far down. This would be though, on a steeper close in approach, not a cross country circuit.

[photofly]

just do what it says in the POH. it's really not complicated.

[iflyforpie]

Not always.

When I used my 206 POH recommended approach speed of 80-90 MPH.... even when heavy and at the low end of the range it would land flat. It has a Sportsman STOL, but unlike the Robertson it does not modify POH speeds. I found that going down to 70 MPH for even full loads made the plane land much nicer.

[photofly]

sounds like a problem with the STOL documentation. For the 150, 152, 172 and 182 POH speeds work very nicely.

[Lotro]

I love you guys, really I do, but sometimes this low-timed wonder is left scratching his head...

From a 172S POH

NORMAL LANDING
1. Airspeed - 65 - 75 KIAS (Flaps UP)
2. Wing Flaps - AS DESIRED (UP - 10° below 110 KIAS,
10° - FULL below 85 KIAS)
3. Airspeed - 60 - 70 KIAS (Flaps FULL)
4. Elevator Trim Control - ADJUST
5. Touchdown - MAIN WHEELS FIRST
6. Landing Roll - LOWER NOSEWHEEL GENTLY
7. Braking - MINIMUM REQUIRED

From a 172N POH

NORMAL LANDING
1. Airspeed - 60 - 70 KIAS (Flaps UP)
2. Wing Flaps - AS DESIRED (Below 85 KIAS)
3. Airspeed - 55 - 65 KIAS (Flaps DOWN)
4. Touchdown - MAIN WHEELS FIRST
5. Landing Roll - LOWER NOSEWHEEL GENTLY
6. Braking - MINIMUM REQUIRED

From a PA-28-180 POH

The airplane should be trimmed to an approach speed of about 85 miles per hour with flaps up... Reduce speed during the flareour and contact the ground close to the stalling psee (55 to 65 MPH)

From an L4B/L4A/J3 POH

Glide at 60MPH

I've never encountered a notation anywhere that said approach speed changes based on weight of the airplane. All of my instructors taught me approach speeds from the POH and most suggested it's better to carry a little extra speed than less speed in case of gusts, wind shear etc. No one has showed me how to adjust my approach speed, most have recommended the POH number and shown me how to use my eyes to ensure I make the field.

If not from the POH, how is one to judge an appropriate approach speed?

[photofly]

Don't "carry a little extra speed".

172S and C182: 65kts is lovely. A couple of knots more if you're heavy, a couple of knots fewer if you're light.

172M/N 60kts is a treat: a couple of knots slower if you're light, a couple of knots faster if pushing max gross.

It's not hard. Knowing that approach speeds vary with weight is basic basic piloting knowledge.

Then try with the ASI covered up, and learn how the elevator feels at the right speed.

[Rookie50]

In a 172 S, even 65 is too fast. It'll float all day at 70 in ground effect. 60 max, 55 even better if lighter has worked for me. I think POH speeds can be a touch high.

[photofly]

Work out 1.3Vs0, correcting for landing weight and, quadratically for CofG position taking into account tailplane up/downforce. It gives you the POH figures.

[trey kule]

To fast on final? Slow down.
In most light planes if you fly final to fast, the plane will let you know when you get into ground effect.

The POH is a good starting point. Never really understood the 1.3 thing, unless you climb in a plane and have no idea what the stall speed should be. i suppose you could do a stall or two to get an idea.....but....1.3 with power and 1.3 without power will typically give you different results both in the approach, and the landing. Precise speed control with minor power adjustments to get you to where you want to be should be one of the main objectives of the approach.

Instead of trying to figure things out on paper, sometimes it is better to just climb in the plane and do an hour or so of circuits. Try different speeds and power settings for the approach. Get the feel of the plane and how things like the elevator effectiveness is affected by speed. Learn how to control. Speed precisely, hopefully without any wild adjustments

[fanspeed]

To fast on final? Slow down.
In most light planes if you fly final to fast, the plane will let you know when you get into ground effect.

The POH is a good starting point. Never really understood the 1.3 thing, unless you climb in a plane and have no idea what the stall speed should be. i suppose you could do a stall or two to get an idea.....but....1.3 with power and 1.3 without power will typically give you different results both in the approach, and the landing. Precise speed control with minor power adjustments to get you to where you want to be should be one of the main objectives of the approach.

Instead of trying to figure things out on paper, sometimes it is better to just climb in the plane and do an hour or so of circuits. Try different speeds and power settings for the approach. Get the feel of the plane and how things like the elevator effectiveness is affected by speed. Learn how to control. Speed precisely, hopefully without any wild adjustments

Too

[Colonel Sanders]

What I look for in a pilot is an ability to
control the airspeed. At first, I don't really
care what it is.

But when I tell him to maintain 75 on final
after wings level, I don't want to see 70 or
80. And I want him to maintain 75 even when
he pitches up or down to keep on the glidepath.

This simple skill is lacking in many. But once
he can control the airspeed, flying the right airspeed
is pretty trivial.

Many pilot are pretty lax, and don't care if they're
on the centerline or not, which bugs me. Large variations
in airspeed are normal for them.

If they cared, they could make the airplane do exactly
what they wanted. Instead they just slop along, and
complain that their landings are mysteriously not working
out for them

This is probably 'way too far out there for this thread, but
for me, the trend of the airspeed is actually more important
than it's old instantaneous value, which is rather historical.

The trend of the airspeed tells you what's going to happen
in the future, and that's pretty interesting to me. If you ever
intend to fly an airplane that weighs more than 1000 or 2000
lbs, you will find this to be increasingly important, especially
if it is slippery.

I am rather proud that I didn't use the word derivative once
in this message.

[trampbike]

I am rather proud that I didn't use the word derivative once
in this message.

Why would you want to integrate such a term in the discussion?

Ba Dum Tsss!

[PilotDAR]

Work out 1.3Vs0, correcting for landing weight and, quadratically for CofG position taking into account tailplane up/downforce. It gives you the POH figures.

Huh?!

Or, just fly the plane with attention to flying the speed you intend. If you fly a speed which is too close to stall for the configuration and weight, you'll probably get a stall warning. If you're not getting a stall warning, and you are unaccelerated, the plane is flying safely, though you might not have enough reserve of speed for a perfect power off flare - when you do try to accelerate (upwards).

The manufacturer has worked out comfy speeds, which will take you safely through the approach for all referenced configurations. The manufacturer has also built in a safe margin for you of about 5 knots. So, you can carelessly fly the whole approach 5 knots slow, and the aircraft will be safely controllable (again, you will now need some power to flare).

If you really want to do a whole bunch of math, and arrive at a precise speed for your weight, C of G and tail downforce value (however you quantify that) go ahead. But then, are you taking that speed value, and factoring IAS to CAS from the position error correction table, and then factoring the instrument error from the calibration card for that ASI? Light aircraft manufacturers give you reasonable numbers, which are based upon 1.3Vso, but might not be right on, as they (happily) are not having to give you tables of exact speeds per configuration, as a transport aircraft would - you just don't need a whole bunch of configuration dependent approach speeds for certified light aircraft!

There is zero benefit to working out the detail to the nth degree on one side, and not applying the very real corrections on the other. After all is said and done, those who do, end up chasing the ASI down final to the knot, and not learning the proper view, or feel for the aircraft. I expect to see a pilot establish a suitable airspeed on long final, for which they may reference the ASI. After that, I expect the pilot to fly the approach more by assuring that the "feel" of the aircraft is maintained so as to maintain the speed. A configuration change will restart this quick process. This is much more about pitch force and AoA management than speed.

If you're flying slower than Va, the plane can be stalled at quite a variety of speeds, so until you're coordinated in a slightly descending 1G flare, what you're ASI says is of limited importance. What you feel is pretty important though! Trim the aircraft for the desired approach speed, and then rely upon the design requirement:

Sec. 23.173

Static longitudinal stability.

Under the conditions specified in Sec. 23.175 and with the airplane trimmed as indicated, the characteristics of the elevator control forces and the friction within the control system must be as follows:
(a) A pull must be required to obtain and maintain speeds below the specified trim speed and a push required to obtain and maintain speeds above the specified trim speed. This must be shown at any speed that can be obtained, except that speeds requiring a control force in excess of 40 pounds or speeds above the maximum allowable speed or below the minimum speed for steady unstalled flight, need not be considered.

That requirement assures that certified aircraft let you feel them slowing or speeding up, so watching the ASI is less important. If you have to pull to maintain your glide path, you have slowed, and you have to increase the elevator displacement to maintain the same tail downforce for that attitude at that slower speed (all other things being equal). In this way, aircraft are pleasingly designed to relieve you of having to maintain and watch of the airspeed. Just watch your aiming point, and feel the pitch control force. If it all staying as you set it when you did reference the speed, you're still on speed.

All of this is design to allow the pilot to get to the ground at the proper speed, if the plane is flown with good alertness. Once near the ground, a flare to arrest the rate of descent, get the attitude correct for touchdown, slows and settles, and you're there.

[Rookie50]

I suspect ingrained by FTU's is an overly ingrained fear of stalling. Likely going to get it for this, but it is really, really hard straight and level to stall a light Cessna single. Add any power at all, it takes forever.

So students see 60-70 on the POH, and always use the highest number, even at light weight. Short final, a light single should have lots of margin at even 1.2 vso, if it's calm. I know organizations that train to fly into very short one way strips, train to fly final approaches, power on with the stall warning lightly chirping on short final.

[Colonel Sanders]

overly ingrained fear of stalling

You have a good point that rarely do you see anyone
do a wings-level stall on final, with the nose pointing
up at the moon.

What is a problem in some types is developing a sink
rate on the back side of the power curve which is
unrecoverable at low altitudes. Ask the guy that landed
the T-33 short of the runway at Hamilton.

Hershey bar wing Cherokees are famous for this, too.
I know an instructor, many decades ago, that watched
his student set the world record for short field landing
in a Hershey bar wing Cherokee when they hit a
snowdrift short of the runway threshold with full throttle
(too little, too late).

Sure, the fear of stalling has something to do with it,
but I think the main problem is complete incompetence
at slow flight. Their instructors don't like slow flight,
the lesson is rushed through once, and they simply don't
have sufficient practice at slow flight, which is exactly
what they are doing in the flare.

They simply can't precisely control their aircraft during
slow flight, so their landings are fast, and they suck.

I am sure that I am a Bad Man (tm) but something I do
to amuse myself in the Pitts on occasion is to quickly enter
full power slow flight on downwind when I need to make
some space between me and the guy ahead of me. There
are other techniques, but this one is fun. Walk the rudders
and flip the smoke on.

Now, pilots who are incompetent at slow flight will think
that I am a Bad Man (tm) and I'm ok with that. If they
want to stop by and give me any stick & rudder pointers,
I'm all ears.

[photofly]

Work out 1.3Vs0, correcting for landing weight and, quadratically for CofG position taking into account tailplane up/downforce. It gives you the POH figures.

Huh?!

...

The manufacturer has worked out comfy speeds, which will take you safely through the approach for all referenced configurations.

Sigh.

That was precisely my point. Sorry you missed it. I accept that you think I'm an idiot, btw, and I'm ok with that. It's easy to beat low expectations.

[Colonel Sanders]

It's easy to beat low expectations

Yes, but my money's still on Chad Smith.

[slam525i]

overly ingrained fear of stalling

You have a good point that rarely do you see anyone
do a wings-level stall on final, with the nose pointing
up at the moon.

Some of this is because some of the instructors are FTUs have a flawed understanding of light aircraft design, possibly because they all dream (or dreamt) of flying big-iron.

I had one during a rental check-out on a 152 that freaked-out during a standard flare-and-hold-it-off. He was convinced a full-stall landing would result in a tail-strike.

(Beware of anyone who uses every available opportunity to tell people that they're a Class 1 instructor.)

[PilotDAR]

I accept that you think I'm an idiot, btw, and I'm ok with that. It's easy to beat low expectations.

Oh, all to the contrary, I assure you.... I read much of what you post with interest and agreement.

However, I occasionally read posts with analysis of how aircraft fly, which in my modest opinion delves much farther than would be helpful to many readers here. Though possibly truthful, needlessly confusing and distracting. Aviation is filled with immense analytical background, but behind that has to be some pretty basic and sound flying. It's fine to sit on a rainy day, and work out on paper how and why a plane does what it does, but that cannot be allowed to overtake basic hands and feet skills, and how they apply to getting the desired performance or handling outcome.

I am not a math person, so I respect those who are. But you don't need math to make a plane fly well. I have known people who could not read and write, much less than do math, and their flying skills were excellent. Many planes I have flown had little or no flight manual, you used your flying skills to work out how to fly it, then build on those skills to fly it better. In our information age, people gravitate toward the "data", and some instructors let them away thinking that will do, in place of basic flying skills - it will not, it's only a part for a properly skilled pilot.

The speeds in flight manuals should be referenced during flying, as they are the manufacturer's recommended practices. However, these speeds are often established on a basis other than optimum aircraft performance and handling. A proficient pilot, exercising good skills, might find that the aircraft will handle and perform very well with references other than those speeds too. You'll find this out, when an instructor puts a sticky over the ASI. That said, in some cases, a speed is established not because that maneuver requires that speed, but if something goes wrong during the maneuver, you'll really want to be at that speed already!

[photofly]

However, I occasionally read posts with analysis of how aircraft fly, which in my modest opinion delves much farther than would be helpful to many readers here. Though possibly truthful, needlessly confusing and distracting.

Well, fair enough. Colour me purple but I don't feel any responsibility whatsoever* to be helpful to many (or any!) other readers here, or any need to avoid confusing people or distracting them. That might make me a horrible person, but I'm ok with that too.


*Really, absolutely none.