transition for a 152 to a 172

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rtbayne01072

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flyboy72
Two days ago I was finally able to go up for another lesson after a month. Thanks to mother nature and my work schedule I had to cancel the last two. My instructor told me a few days before that the 152 I typically trained in was down for maintenance, and offered to take the 172 instead. So with the threat of bad weather the next week I opted to rent the 172. I figured there would be some differences by boy I was shocked when we took off... here are some of the biggest things i noticed during my hour lesson.


1. torque effect- I hit full power on take off and If it wasn't for my instructor then we would have been way off to the left and into the grass in the grass. I somewhat felt the torque effect in the 152 but not near as much as in the 172.

2. Everything seemed to happen so fast- I guess this comes with the territory when flying a bigger and fast plane. While flying traffic pattern and doing touch and goes the time from one end of the down leg to base-to final seem like nothing. I felt very rushed to get set up for final at times.

3. Couldn't flare to save my life.- For whatever reason I couldn't flare on my landings to save my life. :mad2:. I would balloon because I'd try to force the plane to the ground or wouldn't hold the nose off long enough and hit hard. I had just gotten it down in the 152. My only good land was the last one and this was after my instructor told me to trim the nose up some. Also final speed was around 75 to 80 kts. Is that a little fast?

The rest of the lesson was rather uneventful we just departed to the North and did some emergency procedures (power on stalls power off stalls, emergency approach etc.). The one thing that did freak me out a bit was when my instructor did a spin after power on stall :yikes:. All this to say It was frustrating at times but I enjoyed getting to take up a 172 for the day. I'll probably stick to the 152 when it get out of maintenance but still think I need to build some more confidence before taking up the 172 again.
 
Really?

Was this a clapped out low compression 152 to a 172XP 220HP?

I've transitioned folks from one to another in a flight, never thought it was much of a transition.

For what it's worth the 150/2 is a way better single or two person local area bore holes in the sky plane, 172 is good for 3 people and is a little faster and heaver for cross countries.
 
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rtbayne01072 said:
Also final speed was around 75 to 80 kts. Is that a little fast?
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Definitely too fast. CFI should have provided you the V speeds for that C-172 and you should have written them on a cheat-sheet for your knee pad. I think 60 kts for most model years would be acceptable - similar to what you should have been doing in the C-152.
 
I like to approach at 55 in a 152, 60 in a 172, and 65 in a 182, each with two up front (well, 1.5 in the 152) plus full fuel.

See the short field landing checklist if you want to minimize float.

If you can't flare in a 172, you're not trimming.
 
I had to look over at the name and make sure I didn't make this post.. I did the exact same thing my last lesson which was about a week ago. I felt behind all day long and it was work keeping that thing from climbing.. I went from a 152 to a 172 with 180 hp conversion… We did emergency procedures also :) Anyways I hope the 152 is back for my next lesson..

Im around hr 8, next lesson we are going to do nothing but takeoffs and landings and I think my big day may be right around the corner
 
I don't believe converted 172s are legal for intentional spins. Should be in the STC and POH addendum if there is any change. Unmodified 172s are only legal in utility category, which for an N means under 2000 lb and nothing in the back seat. Having said that, a dipped wing is well short of a spin
 
Only time I've landed at 70 in a 172 was a no flap night landing with a CFI. 60 is the usual.
 
Heh sounds like my transition. Gotta use trim a lot in the 172 vs the 15x. I tended to let it climb too much cause I wouldn't trim quick enough, and it does feel a lot faster compared to the 150. After my first three landings I found the 172 easier to land smoothly. My issue with landing was flaps, at flaps 40 the 15x dropped like a rock where the 172 didn't.
 
75-80kts is way too fast, that is one of the reason things are happening faster, and that is too much energy in the plane for a good flare.

For 2 people in a 172, 60-65 mph should do just fine. A 172 at gross may be a little bit more.
 
I trained in a 172 and never went faster than 70 on final. Since getting my ticket I've moved into an archer II. Still fly the 172 every now and then if people want to sight see, it's a fun bird I think (in my complete newbie, uneducated, very little aviation experience)
 
The pattern speeds for a 172 are almost no different than the 152. The plane is certainly capable of going much faster. But you don't do it in the pattern. I made the same mistake when I went from a 150 to a 172. "Holy crap this thing is going so fast, I can't keep up." Then I realized it's going so fast in the pattern due to pilot error!

Climb out at 75-80kts. Reduce power to 1800-1900 rpm, slowing and leveling off at 70kts in the pattern. Abeam the numbers, begin your descent by reducing power to 1100-1400 rpm, flaps 10, and slow to 65kts. Flaps 20 and 60kts on base. Flaps 30 and 50-55kts on final.

At max gross, final is 55kts. But less weight means a lower stall speed, and most training flights in 172 are hardly close to max gross weight. Solo would be more like 50kts. Two people, more like 52-53kts. It may seem like nitpicking knots, but those few knots are the difference between floating and nailing a landing. Those few knots worth of precision could save your life on a short runway or emergency. If you come careening back to earth with 10+ extra knots, the thing will never land. You will balloon and float.

Also, please bear in mind whether your airspeed indicator is in KNOTS or MPH!!! There is a big difference. If you ASI is actually in MPH, multiply all the numbers above x 1.15 to get the MPH equivalent.
 
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Is your ASI in MPH? That seems awfully fast.

I also found that older (172A & 172B) 172s are really nose heavy and a high forward CG. Our club has a 1956 172A that lands like a truck.
 
What does it mean to be "nose heavy?"

I hear it all the time. Honestly, if you notice a difference and you're within CG limits, you are not trimming. Excessively forward CG is another matter entirely, but that really shouldn't be happening with due diligence (and it's not easy to do in a 172).

Trimming is the essence of precision. You'll do all kinds of bad things if you skip that.
 
DesertNomad said:
The 172P book I have says 61kts for a short field. 55kts seems pretty slow.
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Are you sure you're not showing MPH? That is way too fast for knots. The older K/M/N models are all in MPH. Not sure what the P is listed as. 61kts is 70mph. If you try to land a 172 at 61kts / 70mph on a short field, it might just be the last thing you do.
 
On a short turf strip I visit, I'm full flaps and 63 MPH over the fence in my G model..
 
Pedals2Paddles said:
Are you sure you're not showing MPH? That is way too fast for knots. The older K/M/N models are all in MPH. Not sure what the P is listed as. 61kts is 70mph. If you try to land a 172 at 61kts / 70mph on a short field, it might just be the last thing you do.
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Nonsense. All N's are in knots. Some M's are as well.

And the N's short field approach speed is 61 knots indicated airspeed.

It works OK unless the aircraft has been modified.

If you want a real short field landing, the technique is to get way behind the power curve and drag the hell out of it with a lot of power. But that's not a good idea to teach to a student pilot, as it doesn't leave a lot of room for screw ups.
 
I know the POH says 61kts or 70mph. However, the design and flight characteristics are basically the same. And if you do the math correctly using IAS and CAS, 1.3xVso is the same on a N/P as it is on a K/M. The POH says to land at 61kts. But the math says says that is too fast. The math says to land at 50-55kts depending on your actual weight. And it works remarkably better if you do what it the math says.

61kts is too fast. Heaven help the poor guy going 70kts!
 
Pedals2Paddles said:
I know the POH says 61kts or 70mph. However, the design and flight characteristics are basically the same. And if you do the math correctly using IAS and CAS, 1.3xVso is the same on a N/P as it is on a K/M. The POH says to land at 61kts. But the math says says that is too fast. The math says to land at 50-55kts depending on your actual weight. And it works remarkably better if you do what it the math says.

61kts is too fast. Heaven help the poor guy going 70kts!
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A 172 with flaps down is by no means slick. It's easy to shave 5-10 knots off in the last 50 feet. No way I would fly the entire final at 50-55 knots because well that'd take forever. But I will be ditching speed in the last 50 feet so I can touch down with as little energy as possible.

I have no idea what speed I fly a 172 at on final and I instruct in them. I don't put a ton of focus on speeds with students either. I teach them to feel the airplane. Some people demand a number in that case I'll give them one. But I teach them eyes outside and feel the airplane for the last few hundred feet AGL and they eventually decouple from the airspeed indicator as their skills develop.

Flying a "speed" becomes a lot more important in a really slick airplane or if you move to up airplanes much heavier than a 172...

Landing is really about pitch, power, AoA, and energy. Best way to determine that in most of these airplanes is by keeping your eyes outside, hand on throttle, and hand on yoke.

If a student obsesses over the airspeed indicator I put an instrument cover over it and we spend however much time it takes doing takeoffs and landings without it until they really know how to feel their energy.
 
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I did something similar on my 6th lesson. The C150 was down so we took the 172. We spent about 45 minutes doing touch and goes and the instructor signed me off for my 1st solo. So I did my 1st solo in an type that I had less than an hour total time in.

To be fair this was 27 years ago, I was a 20 something kid that had been reading about flying longer than I could actually read, and had being flying RC gliders and airplanes for a few years.

Now that I am an instructor it would have to be a special case for me to solo anyone with that little time, let alone in a new type of airplane.

Brian
CFIIG/ASEL
 
jesse said:
A 172 with flaps down is by no means slick. It's easy to shave 5-10 knots off in the last 50 feet. No way I would fly the entire final at 50-55 knots because well that'd take forever. But I will be ditching speed in the last 50 feet so I can touch down with as little energy as possible.

I have no idea what speed I fly a 172 at on final and I instruct in them. I don't put a ton of focus on speeds with students either. I teach them to feel the airplane. Some people demand a number in that case I'll give them one. But I teach them eyes outside and feel the airplane for the last few hundred feet AGL and they eventually decouple from the airspeed indicator as their skills develop.

Flying a "speed" becomes a lot more important in a really slick airplane or if you move to up airplanes much heavier than a 172...

Landing is really about pitch, power, AoA, and energy. Best way to determine that in most of these airplanes is by keeping your eyes outside, hand on throttle, and hand on yoke.

If a student obsesses over the airspeed indicator I put an instrument cover over it and we spend however much time it takes doing takeoffs and landings without it until they really know how to feel their energy.
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All this sounds right to me! I'm 65 over the fence in everything just in case it gets a hair in its throat on final. ( fifty-fifty five is asking for trouble if something happens, too slow for me. .) it's easy to bleed off speed in a 172, it's a very docile easy to fly airplane, especially if full flaps are used.) I enter the pattern usually at 70, stay in close while turning final , losing altitude quickly, and slow to around 65. I land a mooney the same way and touch down as if I was in a champ or a Stearman, trimmed way back, wheel way back. Never look at the panel. I feel what's going on. It's worked very well for 4500 hours. Landing is my favorite part of flying. Most interesting. Always challenging. I was taught, always use the radio, always spend as little time as possible in the pattern as this is where someone can easily kill you. ( one must know the mooney and slow it down or it will float a lot. 65 over the fence, full flaps, 2000 foot runway) no problem.
 
Our club 172A is nose heavy, meaning that even when trimmed on final, it takes a lot of back pressure to flare. We have to put ballast in the back if we have someone in the right seat. I don't know if all early 172 are that way, but ours is.

I suppose I could trim during the flare...
 
Pedals2Paddles said:
I know the POH says 61kts or 70mph. However, the design and flight characteristics are basically the same. And if you do the math correctly using IAS and CAS, 1.3xVso is the same on a N/P as it is on a K/M. The POH says to land at 61kts. But the math says says that is too fast. The math says to land at 50-55kts depending on your actual weight. And it works remarkably better if you do what it the math says.

61kts is too fast. Heaven help the poor guy going 70kts!
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It works a lot better if you do the math correctly.

The CAS/IAS calibration varies from big to you-gotta-be-kidding-me at the dirty stall speed, depending on model. It's pretty small at approach speed.

Your indicator reads, not surprisingly, indicated airspeed. That 1.3 Vs0 is in calibrated airspeed.

And if you do the math from indicated airspeed through CAS on an N at max gross and max forward CG, you get 60 KIAS. Not 55. You get 55 (or, on P/R/S models that have even bigger calibrations, 50) if you assume CAS = IAS. It's wrong.

You will get a shorter landing with a slower approach speed. But, especially with students, there is a such thing as too short. Generally, defined by breaking stuff as you drop it in.
 
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I did do the math correctly. CAS stall x 1.3 and convert the result to IAS. But I compared using the aft cg numbers since that's all the older models list the speeds for. Keeping it apples to apples.

The speeds are the same. I just use the math rather than the book's vague non specific and rather fast number. But I do get the margin of safety for new students.
 
Well, I just did a bunch of calm wind landings -- light -- in a 172N today, and got some pretty good (definitely PTS) short field landings at 60 KIAS with 40 deg flap. Power off approach was steep as hell in that configuation, but that was the idea. Aimed at the 31 numbers, turned off twy B at KPAO. That's about 800 feet combined float and ground roll.

It's pretty hard to get an aft-limit CG in a 172 without loading a lot of ballast. Today, I ran 1960 lb and 39.5 in CG. I've never been able to get a 172 much beyond 41 inches without ballast. You could get to 44 or so with two adults in back and an empty right front, but who does that? Aft limit is 47.3 at all weights.
 
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I haven't flown a 152 in a few years but my transition was pretty simple. I was still a pre-solo student moving on because of some MX issues. The ground lesson on the 172 was something like.... add 5kts to your speeds, it feels heavy but is more stable, use trim, you will like the stalls more in this one. Sure enough, that was about it.

On the short field topic, 60 kts on final for normal landing, 55 kts for short field with two FAA sized adults on board. The difference is a noticeable difference in the angle of descent. The 55 kts feels more like an elevator going down. Didn't like it to begin with but when flying over an actual stand of trees, it was great.
 
The biggest difference I remember is how your knees feel when you climb out.
 
WingNut42 said:
The biggest difference I remember is how your knees feel when you climb out.
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You mean like how on a 150, you can completely forget right rudder with barely any difference? And on a 172 it will drive off the left side into a corn field...


<< Sent from my mobile device at 0agl >>
 
Pedals2Paddles said:
You mean like how on a 150, you can completely forget right rudder with barely any difference? And on a 172 it will drive off the left side into a corn field...
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And on a 182 you do a pretty good simulation of a ground loop ;)
 
In a 172 I fly as follows:
Downwind I fly 85-90knots
Abeam the numbers throttle back to 1500rpm trim, 10 degrees flaps, trim for 80 knots.
Turning base 20 degrees flaps, trim for 70 knots
Final 30 degrees flaps trim for 65.
Short fields final goes to 60 knots.

Somewhere around three hundred ft my eyes stay outside and I land on feeling.
 
Definetly a high approach speed, 65kts is usually what i approach with, but it varies on how you are taught, some may use 60kts. What i have learned is give it some nose up trim before landing to assist in an easier flare as the controls are heavier.
 
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