All
Well... I went out to a grass strip the other day and measured the distance between the lights. Then I practiced a few landings and take-offs. Here is what I got with a standard C-170B.
Landing-200' is the best I can consistently do. This is flaps 40, and the tail is definately hitting first. I have read that a tail low wheel landing can be the shortest but I don't have the skill to do it yet, with that technique I end up at about 250'. This was on grass and hard ground/basically frozen, no wind, about 30 gal fuel, no VG's or any other mods, temp at about30F. What should I be getting? What techniques are you guys using to max perform your airplanes. If I go to double pucks will the tire rotate on the rim? How do I prevent that?
Takeoff- the best I can do is about 390'. Thats a Tail low T.O. popping the flaps. Same conditions as above. Prop is a 76/55. I was getting about 2250 static. I know a lower pitch prop would help. Again what is the standard? What are you guys getting?
You guys with all the mods, what works and what numbers are you running?
Thanks
Bill
Max Performance Landings
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Your landing and take-off distances seem about right. However, I think you either have one helluva potent engine or someone has depitched your prop from a 55 incher. 2250 static RPM with 55 inches of pitch is pretty high. Sounds more like 55 or even 53. 390 feet is an awfully short take-off run for a 55. Unfortunately, a stock engined C-170 can always get into fields much too short to get out of other than on a truck or trailer.
BL
How are you getting 2250 static rpm with a 55 pitch prop?
What is the length of your prop? Did you measure your RPM
with a strobe/rpm tester?
With a 7653 prop, I barely got the lower end of the limit per the
TC sheet (2230 rpm).
I had one of my props re-pitched to a 51 and that now turns 2450
static (don't tell the feds, K?).
I also have a 48 pitch prop that turns 2600+ static (again,
don't tell the feds!).
I haven't measured it (I need to do that) but your numbers seem
pretty close (landing/takeoff performance).
My '54 has a Sportsman STOL kit, aileron gap seals and I'm running
double-puck brakes with 850 tires. I've had no troubles with the
tires rotating on the rims or anything like that (painted a stripe
which extends from the tire sidewall to the wheels upon installing the
double-puck/850 conversion and nothing has moved).
If I want to land short, I use a tailwheel low approach & once
the mains touch, I stick it on with a little forward pressure and then
balance maximum brakes with whatever aft yoke pressure is
required to keep the tail just off the ground. This has the effect
of putting max weight on the mains which is what you want. Also,
as soon as possible, I dump flaps 40 (to zero) upon touchdown.
With the STOL kit (& relatively light weight of my 170), aerodynamic
breaking via flaps 40 is not as effective as dumping flaps (getting
max weight on the mains ASAP) and standing on the brakes.
As someone else said, you can get a 170 into impossibly tight
places that you'd never get it back out of again....
Bela P. Havasreti
'54 C-170B N170BP
What is the length of your prop? Did you measure your RPM
with a strobe/rpm tester?
With a 7653 prop, I barely got the lower end of the limit per the
TC sheet (2230 rpm).
I had one of my props re-pitched to a 51 and that now turns 2450
static (don't tell the feds, K?).
I also have a 48 pitch prop that turns 2600+ static (again,
don't tell the feds!).
I haven't measured it (I need to do that) but your numbers seem
pretty close (landing/takeoff performance).
My '54 has a Sportsman STOL kit, aileron gap seals and I'm running
double-puck brakes with 850 tires. I've had no troubles with the
tires rotating on the rims or anything like that (painted a stripe
which extends from the tire sidewall to the wheels upon installing the
double-puck/850 conversion and nothing has moved).
If I want to land short, I use a tailwheel low approach & once
the mains touch, I stick it on with a little forward pressure and then
balance maximum brakes with whatever aft yoke pressure is
required to keep the tail just off the ground. This has the effect
of putting max weight on the mains which is what you want. Also,
as soon as possible, I dump flaps 40 (to zero) upon touchdown.
With the STOL kit (& relatively light weight of my 170), aerodynamic
breaking via flaps 40 is not as effective as dumping flaps (getting
max weight on the mains ASAP) and standing on the brakes.
As someone else said, you can get a 170 into impossibly tight
places that you'd never get it back out of again....
Bela P. Havasreti
'54 C-170B N170BP
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funseventy
- Posts: 230
- Joined: Fri Oct 25, 2002 11:46 pm
The only question I have is how did you measure the landing distance? It doesn't matter what the roll is. It matters where you stop in relation to the end of the runway. So was that 200 ft from the end of the runway? You have to have good spot landing ability to make truly short landings. My test that I use for good performance at my home field is this: The first taxi way at my home airport is 800' from the end of the runway. So the goal is to touchdown, stop, and take back off before reaching the taxi way. That is relatively hard. Our elevation is 2200' and my stock 170 can do this with two souls on board and better than 3/4 tanks. A 250' landing is a good consistant number. My short record was 165' from the end of th runway with 8 mph winds at 40 degrees and 2200' elevation. Take offs solo are consistent at 400' the short one with a little wind was just under 300' light on gas and solo. I have flown my 170 into the Mile-Hi strip in Idaho that is 5600' elevation' and 500' long - solo, gas and camping gear. I'll post a few pix on the new 170 photo page.
Kelly
Kelly
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zero.one.victor
- Posts: 2271
- Joined: Tue Apr 23, 2002 12:11 am
Well,I can see I gotta go out & work on my short landings! The distances mentioned here seem plenty good,where are you guys planning on going where ya need better STOL? I'm assuming these are all on longer strips,so plenty over-run after the 200-300 foot landing. If you're gonna go into a truly short place,good luck.One of my favorite aviation expressions is "discretion is the better part of valor". It's one thing to land in 300 feet when you have 2000 of over-run,it's another when 500 feet or so is all there is--every inch counts.
Another thought--a lot of the short landings I've seen involve a long,flat,drag-it-in type of approach. Remember,a lot of short places in the real world don't give you that option. You might have to drop it in over trees or whatever,and get out the same way.
Let's be careful out there....
Eric
Another thought--a lot of the short landings I've seen involve a long,flat,drag-it-in type of approach. Remember,a lot of short places in the real world don't give you that option. You might have to drop it in over trees or whatever,and get out the same way.
Let's be careful out there....
Eric
Eric,
I practice short field landings at a normal (or even above what
could be called normal) glide slope with the throttle closed,
#1 because of what you say (there's *always* stuff in the way
at each end of a remote / dirt strip in the mountains) and
#2 because should the engine ever fail on me, I will have
at least practiced the type of approach / short landing that
may save my life in an off-airport landing.
Bela P. Havasreti
'54 C-170B N170BP
I practice short field landings at a normal (or even above what
could be called normal) glide slope with the throttle closed,
#1 because of what you say (there's *always* stuff in the way
at each end of a remote / dirt strip in the mountains) and
#2 because should the engine ever fail on me, I will have
at least practiced the type of approach / short landing that
may save my life in an off-airport landing.
Bela P. Havasreti
'54 C-170B N170BP
-
funseventy
- Posts: 230
- Joined: Fri Oct 25, 2002 11:46 pm
Max Performance landings
All
Getting some good info here.
Blueldr/170BP- I'm not sure of the prop or tach for that matter. Its an older prop and it may have been tweeked at some point. Also, I can't read the difference between 2230 and 2250 anymore. Heck, I'm over 40 now and lucky to see the moose at more than 100 feet. Gets a little sporty sometimes.
Funseventy- measured from end of runway. In this case there is a bobwire fence about 50 feet from the end so gotta be careful dragging it in too much. It is just practice to improve my skills. Zero one victor- these may not be real world figures but you need a goal to practice with and towards so I'm trying to figure out what I should be able to do, relative to others.
Got the 170 up on skis for the first time yesterday. Cool, but sticky snow made for some incredibly long TO runs. First time I've ever felt the 170 was underpowered.
Bill
Getting some good info here.
Blueldr/170BP- I'm not sure of the prop or tach for that matter. Its an older prop and it may have been tweeked at some point. Also, I can't read the difference between 2230 and 2250 anymore. Heck, I'm over 40 now and lucky to see the moose at more than 100 feet. Gets a little sporty sometimes.
Funseventy- measured from end of runway. In this case there is a bobwire fence about 50 feet from the end so gotta be careful dragging it in too much. It is just practice to improve my skills. Zero one victor- these may not be real world figures but you need a goal to practice with and towards so I'm trying to figure out what I should be able to do, relative to others.
Got the 170 up on skis for the first time yesterday. Cool, but sticky snow made for some incredibly long TO runs. First time I've ever felt the 170 was underpowered.
Bill
The static rpm limits listed in the TCDS is with a 7653 prop. Those limits are not applicable to other pitches of prop. There is no problem with higher static rpms on props pitched flatter, so long as the engine limit of 2700 rpm (145 hp) is not exceeded.
Removing them and throwing the bikini's out the window in flight will shorten things (eventually). Do not expect fast turn-arounds with age.
Removing them and throwing the bikini's out the window in flight will shorten things (eventually). Do not expect fast turn-arounds with age.
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Bruce Fenstermacher
- Posts: 10318
- Joined: Tue Apr 23, 2002 11:24 am
George its good to have you posting again. Where does it say this. I'm looking at the TCDS and it does not say the RPM limits are for the 7653 only. It says "Landplane: Not over 2330, not under 2230" Seaplane is different (this is for the McMauley 1A170.)gahorn wrote:The static rpm limits listed in the TCDS is with a 7653 prop. Those limits are not applicable to other pitches of prop. There is no problem with higher static rpms on props pitched flatter, so long as the engine limit of 2700 rpm (145 hp) is not exceeded.
I thought the RPM limits took into account the exceptable pitch range and would preclude you from using say a 7646 or a 7658, both extreme cases.
CAUTION - My forum posts may be worth what you paid for them!
Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
Bruce Fenstermacher, Past President, TIC170A
Email: brucefenster at gmail.com
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zero.one.victor
- Posts: 2271
- Joined: Tue Apr 23, 2002 12:11 am
Max Performance landings
wa4jr
You're right, ya gotta watch the pounding you put that tail through. I would prefer to be able to do the tailwheel low technique, but I'm still working on that. I find that landing, dumping flaps, braking and keeping it from going on its nose all at once is a challenge. I can do it but, at least for now, I can't do it in less distance than a three point. It definately requires a higher level of skill than a regular wheel landing. It is a new skill to be mastered. Speaking of practicing....things to practice.
1 Wheel landings-- Power on say 1500 RPM
Power off wheel landings
No flap both power on and power off
2 3 Point landings-- Power on and power off
3 Turning take-offs If you have intersecting runways,start on one runway and do a turn, up to 90degrees to complete the take-off on the other runway. Watch the ground loop.
4 Slips to a landing--not Full flap
5 One wheel touch and goes, on wet grass, with a slight x/wind you should be able to do a wheel landing and remain on one wheel throughout, using partial power in the middle will extend the ground roll part giving you more time to practice.
You guys have other ideas, or things you practice? Yea, I know this will fan some flames, but I guess I feel you should be able to make that plane do exactly what you want every time exactly when and where you want it too. Time to raise the bar gents, ala old Johnathan Livingston Seagull.
Bill
You're right, ya gotta watch the pounding you put that tail through. I would prefer to be able to do the tailwheel low technique, but I'm still working on that. I find that landing, dumping flaps, braking and keeping it from going on its nose all at once is a challenge. I can do it but, at least for now, I can't do it in less distance than a three point. It definately requires a higher level of skill than a regular wheel landing. It is a new skill to be mastered. Speaking of practicing....things to practice.
1 Wheel landings-- Power on say 1500 RPM
Power off wheel landings
No flap both power on and power off
2 3 Point landings-- Power on and power off
3 Turning take-offs If you have intersecting runways,start on one runway and do a turn, up to 90degrees to complete the take-off on the other runway. Watch the ground loop.
4 Slips to a landing--not Full flap
5 One wheel touch and goes, on wet grass, with a slight x/wind you should be able to do a wheel landing and remain on one wheel throughout, using partial power in the middle will extend the ground roll part giving you more time to practice.
You guys have other ideas, or things you practice? Yea, I know this will fan some flames, but I guess I feel you should be able to make that plane do exactly what you want every time exactly when and where you want it too. Time to raise the bar gents, ala old Johnathan Livingston Seagull.
Bill
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zero.one.victor
- Posts: 2271
- Joined: Tue Apr 23, 2002 12:11 am
Maybe I'm a big chicken,but item number 3 --turning takeoffs-- sounds like trouble to me. That might be fine for a float plane,to jump your own wake on glassy water,but it sounds like a good way to ground-loop in a taildragger. I made many a turning takeoff in my 170 the first few hours I flew it,but they weren't intentional! I got the takeoffs under control,but still make an occasional turning landing,especially with the evil old southeast crosswind at my home field!
Eric
Eric