Can we talk about the 172?

Jim K

Jim K

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And how awful it is? How is THIS the most common plane in the world?
Now that I have that off my chest...

I've been holding off on this thread as I've only put about 2.5 hours and a dozen landings on the thing, but I'm hoping some of you cessna peeps can offer some advice.

The "aircraft" in question is a 1974 150hp 172M. It's ugly and has a lousy panel, but it's cheap and has wings & a motor. It actually runs well and has surprisingly good power. It seems to be very well rigged and happily flies hands off once you get the the trim set.

I'll start with the positives. It takes off and lands very short and is capable of flying at very low speeds. Landing it is laughably easy. Every landing is a squeaker. The stall horn, which I was sure I would hate, is actually really useful.

The list of things I hate is too long write out, but here's the thing I hate the most: the trim. I understand now why people have a hard time understanding trim. In a cherokee, you set a speed with the trim, and the plane generally holds that speed within a fairly wide range of power settings. In the pattern you don't touch the trim; set up your power and speed correctly in the downwind, and each notch of flaps slows the plane down until it settles at vref when you pull in the last notch on final.

In the Cessna I can't find that magic sauce. It seems like changing the flap setting requires a power and trim change. The thing is just all over the place. It's probably me. Any advice?

TLDR: how do you fly the pattern in a 172? Also Cessna bashing encouraged.
 
Jim K said:
And how awful it is? How is THIS the most common plane in the world?
Now that I have that off my chest...

I've been holding off on this thread as I've only put about 2.5 hours and a dozen landings on the thing, but I'm hoping some of you cessna peeps can offer some advice.

The "aircraft" in question is a 1974 150hp 172M. It's ugly and has a lousy panel, but it's cheap and has wings & a motor. It actually runs well and has surprisingly good power. It seems to be very well rigged and happily flies hands off once you get the the trim set.

I'll start with the positives. It takes off and lands very short and is capable of flying at very low speeds. Landing it is laughably easy. Every landing is a squeaker. The stall horn, which I was sure I would hate, is actually really useful.

The list of things I hate is too long write out, but here's the thing I hate the most: the trim. I understand now why people have a hard time understanding trim. In a cherokee, you set a speed with the trim, and the plane generally holds that speed within a fairly wide range of power settings. In the pattern you don't touch the trim; set up your power and speed correctly in the downwind, and each notch of flaps slows the plane down until it settles at vref when you pull in the last notch on final.

In the Cessna I can't find that magic sauce. It seems like changing the flap setting requires a power and trim change. The thing is just all over the place. It's probably me. Any advice?

TLDR: how do you fly the pattern in a 172? Also Cessna bashing encouraged.
Click to expand...
Most every plane I’ve flown requires retrimming after a flap change. I just figured out a couple flights ago I’m better off without it in the lance.

The Mooney, it was add a notch, two pulls on the trim, add a notch, two pulls on the trim. In the 162, it was opposite, add a notch, two clicks of down trim.

I honestly don’t recall in a 172 what I did.

You shouldn’t need to adjust power though in any case. Maybe you’re making it worse changing two things at once?
 
Start with “paint by numbers”, then roll your own. Generic Cezzna:

Set up at X kts in the pattern (at X rpm).

Pull power abeam the numbers to X rpm, flaps 10, speed X kts. Grab the trim wheel at the top and give it one full nose-up “turn” roughly, then fine tune.

Base, rpm same, flaps 20, “one turn” of trim or so.

Final, rpm same, flaps 30/40, one turn of trim.

Power (rpm) for altitude, pitch (trim) for airspeed. If you do it right, you don’t touch power after abeam the numbers. It’s not necessarily power-off.
 
I was going to say they have so many configurations through the years, they can be pretty different. I have flown a 1964, a 1976, a 2001, and a 2010. The 64 can't get out of it's own way, but the newer ones are quite nice. They are nice for taking pictures and the landings are super easy.
 
A 172 will pitch up when flaps are extended. The downwash off the flaps hits the stabilizer. Expect to need some nose-down trim. It's normal.

It is not a Cherokee. Don't expect it to fly like one.
 
Its awful enough that it can be flown (poorly) with little to no rudder input. They feel dopey but its hard to hate something so docile. Trim is difficult and the rpms seem to fluctuate unnecessarily.
 
Haha! I have 224 hours in 172s and your write up is how I feel about PA28s. The biggest difference is the Cessna wants to fly, the Piper wants to fall.

Each time I roll in flaps, I nose down trim a bit (until the plane is quite slow). In the pattern, the magic number for power is 1500rpm. That’ll get you slowed into the white arc for flaps. I hold 1500 until the fence. But for trim, it’s somewhat the same… I’m trimming the whole time to take pressure out of the yoke. Each flap setting is maybe a half swipe or so of trim. The only time I depart from this trim approach is when I’m doing something non standard… steep approach to a short field, or a soft field - both cases I add extra nose up trim.
 
Jim K said:
It's probably me. Any advice?

TLDR: how do you fly the pattern in a 172? Also Cessna bashing encouraged.
Click to expand...

Interesting. Every 172 i've flown, once trim is set in the downwind I leave the trim as is for the whole pattern. My Cherokee requires trim changes on each leg to get the airspeed right..
 
Handling wise, I prefer the PA28, but the 172 is an all around good airplane and offers one of, if not the best training platforms. If they had a little more zip, I’d say they’d be almost perfect for many missions.
 
23103a said:
Interesting. Every 172 i've flown, once trim is set in the downwind I leave the trim as is for the whole pattern. My Cherokee requires trim changes on each leg to get the airspeed right..
Click to expand...

Agree I rarely touch the trim in the pattern on the 172m I teach in. Set the trim for an 80mph climb out. Pull the power back to level off at pattern altitude (~2100RPM) will stabilize at about 90mph. Abeam the numbers pull the power back to below 1500rpm Nose will pitch down add 10 degrees flaps nose will pitch back up and airspeed should stabilize at about 75-80mph. Add more flaps if or as desired,

Brian
CFIIG/ASEL
 
M model so the airspeed is primary in MPH, correct? Here’s how I teach the pattern in a 172M
Downwind 2200 rpm trimmed hands off for level flight should get you around 100 mph.

Abeam the numbers, carb heat on, 1500 rpm, flaps 10, one swipe up on the trim wheel. 90ish MPH

Base, flaps 20, 80ish MPH

Final, flaps 30, 70 MPH, 65 crossing the threshold.
 
kaiser said:
The biggest difference is the Cessna wants to fly, the Piper wants to fall
Click to expand...
I can agree with this. Cherokees take a good pull to get airborne, and when you cut the power fall like a rock. It's like they're scared to be in the air. The 172 takes just the lightest suggestion and leaps off the runway. It makes me think of Mater from "Cars"... dopey smile, tongue hanging out.

I always assumed any light training airplane would be about the same, but they definitely have personality. I MUCH prefer the pipers so far, but I'm sure that's a lot to do with primacy and familiarity.

snglecoil said:
M model so the airspeed is primary in MPH, correct? Here’s how I teach the pattern in a 172M
Downwind 2200 rpm trimmed hands off for level flight should get you around 100 mph.

Abeam the numbers, carb heat on, 1500 rpm, flaps 10, one swipe up on the trim wheel. 90ish MPH

Base, flaps 20, 80ish MPH

Final, flaps 30, 70 MPH, 65 crossing the threshold.
Click to expand...
Yes, it's in mph. This is exactly how I fly the Cherokees, minus the trim change, so hopefully I can make it work.

I take it most people don't use the full 40 degrees of flaps? Have I mentioned how much I hate electric flaps? The original switch & indicator have been replaced, too, so there's no auto-up detent and the electronic gauge seems to be accurate to +/- 10 degrees. "Count & hope" seems to be the best strategy.
eman1200 said:
too easy
Click to expand...
You're no fun
Racerx said:
I'll start....needing to climb a ladder to fuel.
Click to expand...
I thought "that's no big deal, it'll be offset by not having to switch tanks and crawl under the wing to sump", but climbing up there to dip both sides is a real PITA.

Is it normal to have to steer almost entirely with the brakes, or is this one in need of new bungees?
 
Jim K said:
And how awful it is? How is THIS the most common plane in the world?
Now that I have that off my chest...

I've been holding off on this thread as I've only put about 2.5 hours and a dozen landings on the thing, but I'm hoping some of you cessna peeps can offer some advice.

The "aircraft" in question is a 1974 150hp 172M. It's ugly and has a lousy panel, but it's cheap and has wings & a motor. It actually runs well and has surprisingly good power. It seems to be very well rigged and happily flies hands off once you get the the trim set.

I'll start with the positives. It takes off and lands very short and is capable of flying at very low speeds. Landing it is laughably easy. Every landing is a squeaker. The stall horn, which I was sure I would hate, is actually really useful.

The list of things I hate is too long write out, but here's the thing I hate the most: the trim. I understand now why people have a hard time understanding trim. In a cherokee, you set a speed with the trim, and the plane generally holds that speed within a fairly wide range of power settings. In the pattern you don't touch the trim; set up your power and speed correctly in the downwind, and each notch of flaps slows the plane down until it settles at vref when you pull in the last notch on final.

In the Cessna I can't find that magic sauce. It seems like changing the flap setting requires a power and trim change. The thing is just all over the place. It's probably me. Any advice?

TLDR: how do you fly the pattern in a 172? Also Cessna bashing encouraged.
Click to expand...
Wandering trim is a thing in all the 172’s I’ve flown and it’s been a lot of them. Except for maybe some from many moons ago when I was younger and the planes pretty much new. Wanders in straight and level flight. As far as retriming for configuration changes, yeah, ya gotta do it. Becomes second nature after a while. A swipe or two this way or that way when you do this or that. I think the ‘wandering’ might just be because they are all pretty old nowadays and just a little loose.
 
The 172 is one of the all time great airplanes. That said, it may be one of the all time most boring airplanes. It's like a flying minivan. Easy to fly, solid, stable, no vices, the perfect airplane to take Grandma for a ride (which I did, shortly after getting my ticket when I was 17). But I'd much rather fly a 172 than a Cherokee any day (bearing in mind this is coming from the crazy guy who thinks the perfect airplane has a high wing and a low wing, the little wheel in the back, and no roof).
 
Jim K said:
I take it most people don't use the full 40 degrees of flaps?
Click to expand...

I’ll use 40 degrees on short fields with obstacles. That last 10 degrees is almost all drag. Great for steep approaches into short fields. Climbing out on a go around if you forget to retract or in the unlikely event your flap motor decides to give out at that particular moment…not so much.
 
The only other time I flew a 172 besides the .5 on my discovery flight was about a year or so ago when TRocket was working on his CFI flying right seat. After he did a bunch of laps in the pattern he let me have a stab at it. The plane flew just like other planes fly, albeit much uglier. Power adjustments, trim, flaps, speeds. Really the only advice Tony had for me was when to use flaps and speeds on short final. Otherwise if you know HOW to fly an airplane, it pretty much flies the same as the rest, at least in the pattern. If you can get over the embarrassment factor, that is. Stoopid high wing….. Of course maybe I need a few more tries before I learn the quirks, but I really don’t see the need for that, no sir.
 
Jim K said:
I take it most people don't use the full 40 degrees of flaps? Have I mentioned how much I hate electric flaps? The original switch & indicator have been replaced, too, so there's no auto-up detent and the electronic gauge seems to be accurate to +/- 10 degrees. "Count & hope" seems to be the best strategy.
Click to expand...

I love electric flaps. None of these Johnson bar shenanigans… I’m in an aero plane and command flaps with the flick of my wrist!

I only flaps 40 for short or soft field. Go around are an immediate flaps 20 (after power, carb heat).
 
Most of my hours are 172Ms with some SP time for good measure. Its a solid, predictable not particularly stellar at anything except taking you into the skies which sure is way better than driving.
 
kaiser said:
Haha! I have 224 hours in 172s and your write up is how I feel about PA28s. The biggest difference is the Cessna wants to fly, the Piper wants to fall.

Each time I roll in flaps, I nose down trim a bit (until the plane is quite slow). In the pattern, the magic number for power is 1500rpm. That’ll get you slowed into the white arc for flaps. I hold 1500 until the fence. But for trim, it’s somewhat the same… I’m trimming the whole time to take pressure out of the yoke. Each flap setting is maybe a half swipe or so of trim. The only time I depart from this trim approach is when I’m doing something non standard… steep approach to a short field, or a soft field - both cases I add extra nose up trim.
Click to expand...

The PA28s are a step up from the 172. Even when comparing a new Archer LX and the 172s. The reason is the PA28s airframe has more stability refinements that are quite noticeable in all phases of flight, but especially in at 70-90 KIAS airspeed.
 
Pros for me:
I like the shade of the high wing.
Not switching tanks - if I don't wanna.
Love having two doors.
No crawling and sumping.
Stout enough, and easy to help my kids, grandkids, friends, and Young Eagles that want to learn.
Fairly easy to work on, and find parts, upgrades.
Somewhat less yaw in turbulence than the low wings I've flown.
Grass field, no worries.
Good gph burn.
Decent useful load.
Reasonable insurance.
Usually a decent demand if you want to sell.

Cons:
Slow, boring, not sporty looking, need a ladder to fuel, only 40gal. Underpowered at altitude, typically 2-3 person plane, but not always.
I wish it was a 182.

I do like the Pipers too, but prefer the seating, two doors, and shade. I swore during training I'd never buy one due to the speed, but it was offered at price\condition I couldn't pass up.

Johnson bar or electric, either is fine with me. I guess I'm biflapsual.

The little single trim tab is surprisingly effective. The more you fly it the better your trim skills get.
I like 1500rpm until the threshold too.
 
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Most all airplanes require trim changes with every power or flap setting change, it's called physics. The 172 probably requires more than the Cherokee because it's flaps generate more lift where the Cherokee's are mostly drag. I'd rather have the 172 to be honest. To me it's more comfortable, the performance is splitting hairs, and the high wing offers a shady spot to hang out between flights.
 
Salty said:
Most every plane I’ve flown requires retrimming after a flap change.
Click to expand...
The 162 only needs it if you take your hand off the stick yoke stoke. The forces were so light that I hardly ever noticed, especially after coming out of a 182 or Mooney.
 
asicer said:
The 162 only needs it if you take your hand off the stick yoke stoke. The forces were so light that I hardly ever noticed, especially after coming out of a 182 or Mooney.
Click to expand...
Your passengers will not like it if you put flaps in and don't counteract in a 162. I honestly never tried without trimming, but I think your speed would decay way too much without the down trims each time. It pitches up quite a lot.
 
Fly a 172 by the numbers... flaps with small adjustments to the trim
 
Funny thing, when flying the Piper Arrow, the plane just flies straight and level. I cannot determine if the autopilot is operative or broken lol because with it on and off it flies the same. :D

I kind of say I want the autopilot working but if you trim it and it flies straight and level then what do you need the autopilot for unless of course you have a nice one that connects to a Garmin GTN650/750.
 
You don't like it because you have to use trim?

The Toyota Camry is one of the best selling cars on the road.
 
I fly a pair of 172s from the club. I'd love to be flying something more interesting, but they're just fine for putzing around. And the S isn't a terrible airplane - I can get 4 regular sized folks in the plane and fly for a couple of hours, which is about as long as you want to sit in it anyway.
 
Dan Thomas said:
Early 172Ms were in MPH. Later Ms were in knots.
Click to expand...

Yep - our 172M is in knots. Makes it easier for my peanut brain to bounce back and forth between it and the S. :)
 
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