Speeds for Base and Final in a 172...

Snaggletooth

Snaggletooth

Line Up and Wait
Joined
May 9, 2009
Messages
665
Location
Texas
Display Name
Display name:
Dustin
What Speeds should you be at for Base and Final in a 172?? Most of my time has been in a 152, and I was just wondering how much the speeds varied between the 152 and the 172.
 
Snaggletooth said:
What Speeds should you be at for Base and Final in a 172?? Most of my time has been in a 152, and I was just wondering how much the speeds varied between the 152 and the 172.
Click to expand...

How about 1.4 Vso and 1.3 Vso
 
Snaggletooth said:
What Speeds should you be at for Base and Final in a 172?? Most of my time has been in a 152, and I was just wondering how much the speeds varied between the 152 and the 172.
Click to expand...

Dunno the model 172 you're flying but on the N's I trained on it was 70 on base and 65 on final. Drop to 61 over the fence.
 
This is really a good question. However I don't have a real good answer.

I would recommend that you look in the POH and probably find a range something like 60-70 kts or maybe 69MPH

I tend to recommend the middle of the range on final and let the speed bleed off as you slow the decent and start to level off.

Practically the slowest you can do it with confidence and deal with the unexpected is what you want.

Give your self some slack and get comfortable.

Joe
 
Depending on conditions I'll generally be looking for about 70 on base, 60 or 65 on final, dropping to 50-55 over the fence.

The rule of thumb I used when stepping up from the 152 to the 172 was to add 5 knots to all my memorized speeds.
 
Areeda said:
Practically the slowest you can do it with confidence and deal with the unexpected is what you want.

Give your self some slack and get comfortable.

Joe
Click to expand...

Good advice... easier to remember than the "book" speeds for the various models of 172. I've flown four or five different series, and while the numbers are nice to know, worth a look before you fly a new-to-you 172 for the first time, the above summation works best... with any airplane, really.

Compared to the 150 or 152, the usual 172 approach speeds will generally be a little higher. But they can both be flown base and final at the same speeds in each plane with no problem.
For example: I have 2 POHs handy: one for the '68 150H, one for the '69 172K. The 172K POH refers to a "before landing" target airspeed of 70-80mph (clean) and 65-75 mph (flaps down). That sounds about right for the range from abeam the numbers on downwind to short final.

-Incidentally, those speed ranges contain the speeds obtained by multiplying Vs/Vso speeds for that plane by 1.4 (for base) and 1.3 (for final), close to the lower limit of each scale in each case.



Looking at the 150H manual, it's similar:
65-75mph clean, 60-70mph "dirty". Same deal with the stall speeds/ approach speeds relationship.
The lower limits are lower with the 150, but there is some overlap. What's more, a 172K will stall in level flight just below 60 mph, so you could theoretically fly it as slowly on base and final as your slowest 150 approach. And why not, if conditions permit? My 172 landings improved a lot when I started trying to fly slower approaches.

But as for whether you should or not: go back to Joe's quote. :D
 
Last edited:
In my N and I model experience, we used 70KIAS for Base, 65KIAS for final, and then down to 60over the numbers.

Easy enough, if you trim for 75 with 1 notch of flaps when abeam the numbers, after turning base the next notch of flaps should take you to about 70, then turning final, hit that next notch of flaps.

Easy as pie. That's why Cessnas are used for training :D
 
Better yet, don't even look at the ASI -- just keep the plane in a zero-pitch attitude with 20 flaps on base and full flaps on final -- the speed will take care of itself.
 
Ron Levy said:
Better yet, don't even look at the ASI -- just keep the plane in a zero-pitch attitude with 20 flaps on base and full flaps on final -- the speed will take care of itself.
Click to expand...
But if he puts in a slip won't he spin it into the ground??? ;) ;) :D:D

I would say this is a pretty good recommendation once you really get used to your plane. At your stage in training keeping a good scan onto the airspeed indicator is also a good thing.

Upon entering the pattern I want to be at 80k or less, turning bass I am slowing to no more than 70k and on final 60-65k less any gust correction.
 
rottydaddy said:
My 172 landings improved a lot when I started trying to fly slower approaches.
Click to expand...

Oh, man, so many pilots never discover that. We recently retired a later 172M whose POH called for 55 kts on final. If you flew much faster than that, you arrived with way too much speed so you'd do one of several things:
A) float forever and use up lots of runway; B) land while still too fast and therefore flat, risking wheelbarrowing or blowing out the tires when trying to stop an airplane that still has little weight on its wheels; C)ballooning when you flare a bit too much and ending up at fifteen feet with no airspeed; or D) running off the end of the runway. I've seen every one of these things in my time here, and sometimes airplanes get broken.

Excess speed on final adds nothing to safety unless we're in gusty conditions. Even then we don't need a lot extra. And one way to end up with too much speed is to dive at the runway when too high.

Dan
 
Ron Levy said:
Better yet, don't even look at the ASI -- just keep the plane in a zero-pitch attitude with 20 flaps on base and full flaps on final -- the speed will take care of itself.
Click to expand...
Exactly. I understand that the focus on specific speeds in primary training has some advantages, but I really wish my first CFI had not thought specific speeds.

The only speed I really care about is stall speed. In a 172, it's so incredibly easy to slow down (not like you can go very fast to begin with). I fly everything at full power (or below Vlo in a RG) on downwind, gear down at some point, then final with some margin above stall (in VMC). Personally, I think focusing on 65 vs 70 knots, etc., is taking away your focus from more important things.

I know someone who flies a HP RG who never looks at the ASI in the pattern. He's familiar with that plane, but I agree that there's really not that much need to keep looking at it.

-Felix
 
Interesting range of responses. I'm in the camp that likes some monitoring of airspeed but not a lot. Basically set flaps and power abeam the numbers on downwind then get on speed. Add flaps with the turn to base and check airspeed - it'll be about right. Add flaps with turn to final. Check airspeed and pick spot. Manage power to fix the spot and you'll be pretty close to on speed.

Of course that only works perfectly with a perfect pattern. At least it's a starting point.

When I took the CPA's mountain course I was somewhat surprised to learn they had a name for the procedure. They called it the Vern Foster Precision Visual Approach. Heck, I'd been trained that it was just the ideal way to fly the pattern.
 
Oh yeah -- one other thing -- once you set the attitude for the speed you want, trim so it stays there if you let go of the yoke. Then when you reconfigure again (say, putting down full flaps on final), set the attitude for the speed and trim again for hands-off stability.
 
For a 172- take the speed for the 152 and add 5 knots. When you check the POH, you'll find you are almost spot-on.
 
I fly a 150 with MPH and a 172 with Knts. the Numbers are almost the same. 80 on downwind 70 on base 60-65(depending on winds) on final flare at 45. mph in the 150 Knts in the 172. DaveR
 
Ddayle said:
I fly a 150 with MPH and a 172 with Knts. the Numbers are almost the same. 80 on downwind 70 on base 60-65(depending on winds) on final flare at 45. mph in the 150 Knts in the 172. DaveR
Click to expand...

I can't tell you what the ASI reads once level off begins.

A good exercise would be to fly the pattern with the ASI covered (and a CFI on board). Every pilot should be able to conduct normal pattern ops with attention completely outside the airplane and no instruments available.
 
dmccormack said:
I can't tell you what the ASI reads once level off begins.

A good exercise would be to fly the pattern with the ASI covered (and a CFI on board). Every pilot should be able to conduct normal pattern ops with attention completely outside the airplane and no instruments available.
Click to expand...

I remember doing that with the Arrow when I was getting checked out in it and getting my complex endorsement. Listen and feel what the airplane is doing. "Use the Force, Luke!"
 
Sorry if I missed this in earlier posts in this thread:
Depending on the wind component and field condition (ie short field or soft field) my standard configuration is to peg the plane to 85kts past the numbers into base 10/flaps, on base leg 20/flaps 75kts, on final trimmed to 65kts 30/flaps on short final (even though 71D has 40/flaps I have never used them) Of course crosswinds, gusts, LLWS and short field-soft field techniques will require different approach speed & flap combinations
 
Ah yes...weight. I am not a small person (200lbs) Yesterday, flew 71D on a short flight with 2 pilots to pick up their plane at another field from its annual. First time flying with 3 people aboard. Departure runway was 2600 ft, it was standard temp, but I still did a short field T-O, except rotated at 60 kts since there were no obstacles to clear. Front seat passenger was 180, rear seat was 160. The extra 340 lbs made a noticeable difference. Didn't add fuel until after this flight! I thought about the landing config the whole flight!! But actually, the plane handled pretty much as always in the approach, just kept the power settings a bit higher to compensate for the weight. Another learning experience.
 
I did all of my training in N-model 172's at KSGR. Here's what we used in the pattern:

Abeam the numbers - carb heat on, power 1500rpm, hold altitude to bleed off speed, 10 deg of flap at the white arc, then trim for an 80-knot descent.

Base leg - 20 deg of flap, 75 knots, check that the final is clear and do your first CGUMPS check

Final - 30 deg of flap, 65 knot descent, adjust power to give the proper glide path, do another CGUMPS check - can add the last 10 deg of flap if desired, but maintain 65 knots until the flare.
 
t0r0nad0 said:
I did all of my training in N-model 172's at KSGR. Here's what we used in the pattern:

Abeam the numbers - carb heat on, power 1500rpm, hold altitude to bleed off speed, 10 deg of flap at the white arc, then trim for an 80-knot descent.

Base leg - 20 deg of flap, 75 knots, check that the final is clear and do your first CGUMPS check

Final - 30 deg of flap, 65 knot descent, adjust power to give the proper glide path, do another CGUMPS check - can add the last 10 deg of flap if desired, but maintain 65 knots until the flare.
Click to expand...
How far does it float when you flare at that speed?

The textbooks talk about the "round-out," which comes before the flare. At between 15 and 30 feet the power is reduced and the nose held up so that the speed begins to bleed off. Getting rid of excess speed out of ground effect uses up far less distance than in ground effect, where so many pilots do it. As the speed bleeds off, the airplane will fall faster so you raise the nose a bit more to check that. Keep this nose-raising going, and if you've done it right the airplane arrives at the surface nose-high and without enough speed to bounce or balloon or float. The whole process should be seamless, with the round-out becoming the flare near the surface.

It's harder than it sounds, and so many tend to arrive a couple of feet above the runway with approach speed or something close to it, and then have to wait the the speed to fall off and gingerly feel for the runway lest they balloon or bounce off the nosegear.

Dan
 
DutchessFlier said:
Sorry if I missed this in earlier posts in this thread:
Depending on the wind component and field condition (ie short field or soft field) my standard configuration is to peg the plane to 85kts past the numbers into base 10/flaps, on base leg 20/flaps 75kts, on final trimmed to 65kts 30/flaps on short final (even though 71D has 40/flaps I have never used them) Of course crosswinds, gusts, LLWS and short field-soft field techniques will require different approach speed & flap combinations
Click to expand...
When I flew N5371D I always went to 40 degrees flaps and came in at about 60 knots slowing to about 55 towards the end. YMMV -- changes with weight. Does that thing still have that ****ty GPS and a scratched up panel? One thing I've noticed about those that say they use higher speeds than me is that they start their flare higher which slows them to the speed I use -- they just don't notice it. I tend to start my flare fairly late as I don't have much energy.

These days -- I really don't look at the airspeed much at all. I have no freaking idea what speed I land the PA-28-180 or C-150 I'm flying these days. More or less whatever power keeps me from stalling but doesn't make me float.
 
Last edited:
Dan Thomas said:
How far does it float when you flare at that speed?

The textbooks talk about the "round-out," which comes before the flare. At between 15 and 30 feet the power is reduced and the nose held up so that the speed begins to bleed off. Getting rid of excess speed out of ground effect uses up far less distance than in ground effect, where so many pilots do it. As the speed bleeds off, the airplane will fall faster so you raise the nose a bit more to check that. Keep this nose-raising going, and if you've done it right the airplane arrives at the surface nose-high and without enough speed to bounce or balloon or float. The whole process should be seamless, with the round-out becoming the flare near the surface.

It's harder than it sounds, and so many tend to arrive a couple of feet above the runway with approach speed or something close to it, and then have to wait the the speed to fall off and gingerly feel for the runway lest they balloon or bounce off the nosegear.

Dan
Click to expand...

Not far at all. I did forget to mention that I pulled the power to idle once the runway was made, and the flare does include a round-out as you described. I just assumed that would go without saying. Of course if you come in at approach speed and immediately pull into a flare attitude, you're going to balloon. So yes, technically I level off above the runway, bleed off speed, and keep pulling as the plane slows down until my mains touch down with the nose still in the air.
 
My "L" model is in MPH, and I use 80 on Downwind, 75 Base, 65-70 on final, down to 60 over the fence to touchdown. Also, I've found that with the overhead vents open, I can hear a very distinct whistle at 5 mph above stall speed on final. I can make is just start, and releasing a tiny bit of pull on the yoke will make it stop. Just another que for me. I trim so that I need to hold back very slightly to maintain my target speed. If I need to go-around I can add throttle and it will not give me much pitch up but will get airspeed in a hurry (at least as much as you can in a 150hp 172).
 
This should help:

Vs0 < Vbase/final < VNE
 
Jesse:

I lied...once I used 40 deg flaps to nail a short field bet with my CFI who said I couldn't hit it by the end of the first stripe..I won! (you never saw a flap lever move up so quickly after touching down!!) Never felt the need to do 40 deg again, possibly because I usually have alot of rwy to work with almost everywhere I fly 71D so 30 has been the max...I like holding 65 to the fence, the just let it all bleed off and let gravity do its thing. Also, on a go around, she behaves much better going 30 to 20 rather than 40 to 30.
71D had her panel and interior redone (I believe w/o checking the logs right now) in 2003 and the exterior painted around 9 or 10 years ago. Is the paint scheme in the pic the same as you recall?
As far as the s*****ty GPS...nawwwww thats gone...I installed a Garmin 430W when I brought her back to NY from St. Paul last spring and this week am installing a Garmin GTX330 TIS transponder for traffic info fed into the G430. The panel looks great!
 
You must log in or register to reply here.
Back
Top