Runway length question

4RNB

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4RNB
I dream of having enough land to keep a plane on. Is there a good rule of thumb for an average pilot with regards to minimum runway lengths needed for given/known/assumed/expected performance data?

Thank you.
 
A lot of people use a 150% rule…they won’t take off or land on anything less than 150% of book requirements.

I’ve seen a lot of pilots whose normal technique easily exceeds that…fortunately they don’t actually land on anything that short. Whatever you choose to do, make sure it’s adequate for how YOU takeoff and land, not just book numbers.
 
I dream of having enough land to keep a plane on. Is there a good rule of thumb for an average pilot with regards to minimum runway lengths needed for given/known/assumed/expected performance data?

150%, as @MauleSkinner mentioned it a good starting point. But there are so many variables. Is it a one way strip? Do you want your friends to be able to come visit? Are you good about maintaining currency? Is the penalty for an overrun a hassle getting the plane out of the weeds, or is it injury or death? Are there obstructions? Will you be oriented into the prevailing winds? Will the terrain create swirly winds? Will you be on turf? Pavement? Gravel? Do the economics makes sense compared to just buying a house *near* a strip, instead of buying land sufficient for a strip?

This topic can be quite a rabbit hole.
 
Don’t forget to factor in slope (if any), grass condition, obstacles (trees) etc. I would second something along the lines of 150% (or another X factor) over any book performance as an absolute minimum. Throw in a windy crosswind or some other factor and suddenly your runway doesn’t look as long as it does on a calm day. There is a reason a lot of paved runways are least 3000’ in length. Now, the airplane you operate into that private land will play a big role too.
 
Depends on plane and pilot. Around here, 2000-2500 feet is normal for private grass strips. I operated a Stinson 108 from a 1400 foot grass strip years ago..flew a 1955 Bonanza from a 2400 foot grass strip. If the field is short and only one good approach end, some days you elect not to fly.
 
150%, as @MauleSkinner mentioned it a good starting point. But there are so many variables. Is it a one way strip? Do you want your friends to be able to come visit? Are you good about maintaining currency? Is the penalty for an overrun a hassle getting the plane out of the weeds, or is it injury or death? Are there obstructions? Will you be oriented into the prevailing winds? Will the terrain create swirly winds? Will you be on turf? Pavement? Gravel? Do the economics makes sense compared to just buying a house *near* a strip, instead of buying land sufficient for a strip?

Slope too. As you know, my strip is probably at a 3-4% grade, which shortens my landing distance by quite a bit!
 
It depends entirely on what you're flying, how heavy you plan to load it, and how good or how comfortable you are flying it. I took an Archer to a grass strip that was 1900' on my solo cross country and the length of the strip wasn't even a potential problem.

An interesting exercise you might consider doing is real world analysis of how much runway you usually take to land in different configurations, and that might help you get a better idea of what your own limitations are.
 
An interesting exercise you might consider doing is real world analysis of how much runway you usually take to land in different configurations, and that might help you get a better idea of what your own limitations are.

Based on what I have witnessed with the trend toward excessively fast approaches with floaty, long landing rolls, maybe a review of short field technique and a personal assessment of the required landing distances will help clarify the absolute runway length that is comfortable for you.

150% of book distance might work out to be much more room than you have available on a piece of land and that can be a huge factor in determining what airplane and what gross weight will work.

You may not have the willingness to rely on your skills to repeatedly operate out of a short strip. On the other hand, we all want to be Jon Humberd...
 
Depends on plane and pilot.

:yeahthat:

I've used a 1000' grass runway in a Challenger II with a passenger. In my current plane I've been in & out of a 2000' grass runway. It would do shorter than that but I'm quite cautious.

As Doug said it's gonna depend on what plane you are flying and your skillset flying that particular plane. Winds, slope, & runway surface will all make a difference.
 
I used to recommend this for determining takeoff performance…it can adjust for more factors than most POH/AFM data, plus you can normalize your actual performance as a baseline rather than book numbers.

upload_2022-1-13_12-23-25.jpeg
Unfortunately it looks like Sporty’s discontinued it.
 
I built a strip in South Georgia a few years ago. I made it 4650' long because that is what the land I had would accommodate, It is 100' wide with a 75' safety zone each side . Main runway is 18-36. I also have a crosswind runway 05-23 that is only 2000' long with trees at one end. . I fly a Commander 112 (turbonormalized) .
I have pretty well worked with what I had. I have some trees on the South end but they are not on my property. https://www.facebook.com/GOPSASSER

Life is a barrel of fun.

Ken Andrew
 
Do the math, then go out and give it a try! Runway edge lights are typically 200 feet apart. The Aiming Point Markers are 1,000 from the threshold. Use Google Maps to measure to specific landmarks on your airport's runway to calculate distance. See what you and your aircraft are reliably and comfortably capable of. If your strip will have obstructions, note your altitude over the threshold on landing, and note the distance it takes to get to a safe altitude on climb out. Book numbers and math can give you a ballpark, but you will have to determine what you are capable of.
 
Unless you are at a higher altitude or where is gets smoking hot, 2000 feet works well.
 
I'm eyeballing a piece of property with 1200' in the clear, 3600' elevation. That's about my minimum.
 
I'm eyeballing a piece of property with 1200' in the clear, 3600' elevation. That's about my minimum.

Sounds about right^^^^^

I routinely fly in and out of a 1700' turf strip in my 172 with no problem. I only use half of the strip, there is dip in the middle that I avoid. It is only 500' msl. I have been there on 95°f days and recently with a little snow. I notice the grass is a little higher than other turf strips which helps me stop with very little brake.

Would love to have my own grass strip, but then I would miss all the activity at my airport. Might be boring having the place all to yourself?
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Then there is lee bottom in the area, 4100' long with a hill to the west to protect you from the wind. MY buddy said he could land a 737 there. Probably couldn't take off from there cause the ground would be too soft.
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