C172R for ab-initio training?

[mingalababya]

Hi all,
I'm doing my instructor's rating in a C172R and I find it a very nice aircraft to fly. I do notice some differences between the C172R and early model C172's (say the M and N models that were manufactured in the late 70's) in terms of it's handling and performance. Well, for starters, 172R models are about 15 to 20 knots faster in the cruise than the early 172's. I also find that not as much back pressure is required in the 172R's when doing medium level turns compared with the early model C172's.
Also, I find that when doing circuits on base leg, I need to reduce the power right back to about 1000 - 1100 RPM (compared with 1500 RPM with early model C172's) so that I can reach a target speed of 75 knots on mid-base.
Does anyone who's flown both types of C172's agree with me here?
And what's your thoughts on conducting ab-initio training on C172R's? Is it a bit too fast in the circuit area for ab-initio pilots learn the basics in ?

[huckleberry58]

I instructed on both extensively as my flying school had all types of 172's. IMHO it's easier to train on the R's. Firstly, no carb ht to worry about. Only 30degrees of flap makes it easier. I found 1500RPM with F20 still ok on the base leg. Cupholders are a nice touch too.

[heading 125]

Just come back from the states flying a C172 s and yes it is faster and a bit more slippery. They teach in the circuit there to reduce to 1900 RPM with 10 degrees of flap when abeam the threshold late downwind. Turn base at the usual position and then 20degrees of flap and 1600 RPM - 70k

[cherrnkind]

I have just moved to a C172R to finish my training in. I have a problem with it on the ground after landing being hard to control. The 2005 C172R handles very different than the older 172 ,it must have a different wing to dirty stall at 33kts when the older 172 stalls around 44kts. My CFI has tons of time in the older 172 but not in the newer. Any advice? Iv'e been told by another CFI to retract the flaps as soon as all three wheels are on the ground.

[bjornhall]

The 2005 C172R handles very different than the older 172 ,it must have a different wing to dirty stall at 33kts when the older 172 stalls around 44kts.


That is weird... As per the books:
F172N, flaps 40, stall at 33 KIAS, not sure about KCAS
C172R, flaps 30, stall at 33 KIAS = 47 KCAS

I fly both, haven't noticed any ground handling differences after landing, but what would I know... :O

[Nathan Parker]

I have just moved to a C172R to finish my training in. I have a problem with it on the ground after landing being hard to control. The 2005 C172R handles very different than the older 172 ,it must have a different wing to dirty stall at 33kts when the older 172 stalls around 44kts. My CFI has tons of time in the older 172 but not in the newer. Any advice? Iv'e been told by another CFI to retract the flaps as soon as all three wheels are on the ground.

Same wing. Sounds like you're confusing indicated speeds with calibrated. The R model will have a slightly higher stall speed due to a higher max gross weight and only 30 degrees flaps. Retracting flaps during the ground roll is only a good idea if it's very windy; otherwise, it's better practice to wait until you clear the runway. In a complex aircraft, moving levers during the landing roll could lead you to raise the gear some day.

If you're having a hard time maintaining directional control during the landing roll, you're probably landing too fast.

[bjornhall]

Reading again, I am a bit surprised by what is said about the R here, such as it being faster... Doesn't agree with my (admittedly limited) experience, or what is in the POH...

For instance, cruise speed at 4000 ft, ISA: F172N 110KTAS & 7.1 GPH @ 65%, C172R 111 KTAS & 8.1 GPH @ 70%. Is the perceived 15 - 20 kts difference due to old engines, props & airframes? Of course, if you run a 172N at 2300 RPM @ 4000 ft you're at 57% power, whereas a 172R at the same RPM is at 79% power; that would be expected to make a difference...

Just curious and trying to learn...

[mingalababya]

Hey, I didn't realize I got all these responses on this thread. :) Thanks all for your feedback.

bjornhall, at or near MSL, the C172 does 105 knots at 2350 RPM. The C172R's I've noticed cruises at just under 120 knots for the same power setting.

As for other differences, I did notice the C172R has a more pronounced wing drop when doing a power on, stall with 10 degrees flap. Anyone feel the same about this?

cherrnkind, as Nathan Parker has mentioned, the difficulty you have on handling after landing could be due to excessive speed? I use 70 knots on final with 20 degrees flap and 65 knots over the fence with 30 degrees flap. I've not had too many issues with landing the C172R; the flare and hold-off all appears the same as the older model Cessna's.

[Oktas8]

at or near MSL, the C172 does 105 knots at 2350 RPM. The C172R's I've noticed cruises at just under 120 knots for the same power setting

The C172R has a coarser pitch propeller than the C172N. Both have 160hp engines, but at a given RPM the R will develop more power than the N. To compare like with like, refer to section 5 of the flight manual to determine the RPM giving 75% power for each aircraft. You'll find that the speeds don't change much, but the R model is quieter at that speed due to lower RPM.

I tend to target 100kts on the downwind leg in these aircraft, and set whatever RPM is required to achieve it.