My wife and I are discussing buying some property. I told her my only stipulation was I needed enough acreage to put in a grass strip for my 601 XL.

I know each plane is different based on prop and engine combination, gross weight, pilot skill-but generally speaking, what length grass strip are y’all flying out of, allowing for a margin of error and safety?.

I plan to do some research by flying up to a grass strip in Crystal River to get some real numbers but I at least want to get an idea of what to expect....

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Joe Hopwood might comment on this. I know he lives at an airpart in Alabama....2AL1. Hopefully, I'll get to fly in there when I can go visit my daughter in Pensacola.

I don’t fly a 601 but the variables to consider are pretty much universal. Knowing your level hard surface runway takeoff distance then applying these rules of thumb found here:  may be helpful, especially the “runway surface” and “gradient” sections.  I found them to be reasonably accurate operating from my field. If you do move to a grass strip you may want to also consider different tires. Once you gain experience you’ll never want to land on concrete again. Just somethin* about a grass runway. Feels like sport and recreation, not business and rules.

A couple other things came to mind after I posted the above.  The first is obstacles. Mature trees that you can’t cut down for whatever reason, and abut your desired runway property, will add a significant amount of runway length needed. I would add 50% to your required length on top of the other variables unique to grass strips for a non-STOL aircraft if you can’t set your runway thresholds at least 500 feet away from mature trees.  Shorter obstacles such as farm fences aren’t significant.  Another consideration has nothing to do with the aircraft. Maintenance of the runway requires a significant investment of time and money even if it’s “runway ready” and even more money will be required if the condition of the property is more like a farm field than an airport when you step onto it. Also, are you comfortable renting and operating heavy machinery?Depending upon where your property is located, finding someone with the right equipment and skills that is willing and able to prepare your property can also be a challenge. 

... finding someone with the right equipment and skills that is willing and able to prepare your property can also be a challenge. 

Great advice, Jim.  I found that the cheapest (per hour) contractors are sometimes the most expensive because they aren't efficient.  I had to fire my first contractor because he just didn't progress very quickly and my checkbook was smoking!  The second contractor had actually built airstrips before and had an extensive amount and variety of heavy equipment, but more importantly, knew how to operate the equipment efficiently.  In the long run, he actually cost less than the first contractor would have cost to complete the strip.


Hopefully you'll get some input from 601/650 drivers with turf experience, but having built and operated a 2100' strip (TN66) for 29 years, I can lend a few observations about turf airstrips in general ...

When looking for property and to minimize expense, many try to find the smallest acreage they can shoe-horn a strip into.  In a lot of cases, you'll find you need much more acreage than what the actual strip requires to allow for clearance over obstacles if they exist.  Even if the only obstacle is a fence, if there is a residence across the fence, your neighbor likely won't appreciate you coming over their house or yard at low altitude on short final!  And, if there are neighbors nearby, get a feel for the attitudes about aircraft.  Make sure they understand there will be a low frequency of operations and not a busy commercial operation - it only takes one litiginous neighbor to make your life miserable and expensive!  

If at all possible, find a grading contractor who has actually built turf airstrips before.  Most will want to make the strip pool-table level, crown it in the middle, and run ditches along the edges for drainage.  If the area you pick is not relatively flat to begin with (and very flat areas many times have drainage problems!), it is much better and cheaper to allow a few degrees of elevation change and a few degrees of lateral slope and allow natural drainage and avoid prop-busting and gear leg-snatching ditches! 

Plan and build your strip about a year before you actually intend to use it.  That'll allow plenty of time to develop an established turf and you won't tear it up by premature use.

And of course, check zoning, local/state regulations, etc.  I had the luxury of building well within the interior of a large farm, so I had no neighbor issues.  In rural East Tennessee, the county had zero zoning and the state just said, "call the FAA."  The FAA makes it clear they don't "approve" the design or safety of your strip, but that they merely want to ensure that you "don't present a hazard to the national Air Transportation System."  However, if you do register with the FAA, they'll provide you with some basic data such as your estimated altitude, etc., and put your strip on the Sectional and mark it Restricted.  Visitors to Restricted strips are supposed to have asked the owner's permission first, so if an uninvited visitor lands and crashes on your strip, you "might" have a modicum of liability protection since they were technically trespassing.  Also, some claim registering with the FAA makes it an "official" airport and might protect you from an insurance company denying coverage for an incident resulting from executing an "off-airport operation."

My first landing at TN66 was 7/12/1992 and 20 years later, 7/10/2012, I made my first flight of my STOL 750, N750A, from the strip.  I've always said it is one of the most rewarding and satisfying experiences of my life and you'll develop a lifestyle that you won't regret!



I appreciate the information. That’s exactly the information that I needed. We are a couple of years out from making the land purchase but I want it to make the landing strip more than just an afterthought.
I understand the takeoff and landing distance is over a 50 foot obstacle but there are so many more variables to that that it was important that I get some professional advice

Putting larger lower pressure tires on the plane is a good idea within the constraints of it being a 601 and not a 750.

As far as grading the property I had planned to do it myself, putting a 1° Slope in it but the more I think about it it might be better off in the long run to get somebody out there who knows what the hell they’re doing.

That’s exactly the information that I needed. We are a couple of years out from making the land purchase but I want it to make the landing strip more than just an afterthought.

You're definitely on the right track to do careful planning!  Safety can be designed-in to an airstrip by elimination of obstacles, ditches, etc., and having some "run-off room" should you have a misadventure and depart the runway's edges.

When I built my strip, there was a section of steep bank alongside the runway and I kept looking at it and pacing-off the distance to edge of the runway and speculating whether I could possibly snag the bank with a wing-tip if I was on the extreme edge of the runway.  My engineer-cousin observed me and asked what I was doing and I explained.  He replied, "Why are you worrying about it?  Tell the dozer man to come over here and knock that bank down to where you couldn't possibly hit it!"    I did what he suggested and have not had to worry about that bank for nearly 30 years! LOL!   It's just like building your plane - you get in so deep that in the long run, a little extra expense is not really going to make much difference when you look back in a few years!  ;>)


John made a comment about neighbors. I had a field fixed for my ultralight, and had it in really good shape. My tail wheel was about the size of a grocery cart wheel, and I never had any problems during takeoff or landing.

My neighbor had cattle, and during a wet spring, they found a weak spot in the fence, and since the field was soft due to all the rain, they made it look like the moon. He was cheap and wouldn’t repair the fence, so the cattle kept getting in my field. I finally went to the sheriff, who talked with my neighbor. The fence was fixed, but the damage was done. I could have taken him to court, but just let it go. I sold that plane, and the field is too short for my 601.

Just something to consider when planning your field.

I live in an airpark with a 4,000 foot grass strip. The runway is in fabulous condtion, one of the nicest grass strips in New England. As alluded to earlier, obstacles can be an issue. When this place was developed over 40 years ago the trees were all fifteen feet or so high. Now they are about 90 feet high and go right up to the end of the runway. The Association does not control the land beyond the runway ends so the trees are there to stay. With 4,000 feet it is not really a problem, I tell people to treat it as a 3,000 foot strip - that gives you a thousand feet to clear the trees and get down to a normal landing situation and still have 3,000 feet in front of you. For takeoff you have that 3,000 feet to get airborne and clear the hypothetical fifty foot obstacle and then you have another thousand feet to finish outclimbing the trees.

My 601XLB is not yet built but a neighbor built one and I ended up flying it for about 40 hours or so. He was a low time pilot and not comfortable flying a freshly built plane even if he built it so I did most of the intial flying in the plane. Mine is going to be a taildragger with 6.00-6 main tires. His was a trike with 5.00-5 main tires. To my surprise it did okay on the grass. Our runway is exceptionally smooth and nice so my opinion may not compare if your strip is going to be more rustic, but on a nice grass stip it did well. I think it would have been better with bigger main tires but it did okay.

I had lots of available runway and lots of power (he put a Lycoming O-235 into it and hot-rodded the engine a bit when overhauling it) so I cannot say how a more standard build might do. But, with that caveat, I thiink the plane would do okay for you. The wing has plenty of lift and very good low speed behavior so it's a better STOL machine than you might expect but the short surface you are landing and taking off on cannot be too rough - the realtively squat landing gear, relatively low prop clearance with the ground, and the low wing all combine to require fairly even surfaces.

With no obstructions I would have been happy to fly that 601XLB in and out of a 1,500 strip as long as it had fairly smooth turf. With obstructions I would want more runway available. With careful work I expect it could do a thousand feet but would not recommend it, no margins, no room for error or accident.

There are a lot of variables so please take the above as one person's experience flying one particular plane from one particular airport. My input is not general in nature and you will need to develop your own limits and minimums. Have fun! Let us know how you do.

I really appreciate the input.
I know the 601 is a decent off field plane, I just think its abilities have been overshadowed by it’s STOL-specific stablemate.
My plane is a pretty standard XL with the exception of being a tail dragger. I also put on the standard 5.00x5 wheels and tires (I guess I’ll be taking the wheel pants off)
I have an unmodified O-235 swinging a 3-bladed Catto prop.
If this all comes to fruition, I can swap out the tires to 6.00x6’s. I would also call Catto and get a 3 or 4 bladed climb prop (a 4-bladed prop might provide a bit more ground clearance)

As of right now, I’m pretty lazy with my flying, I fly out of a well-maintained paved ~5000’x100’ strip with clear approaches from either direction (KZPH) I rotate at about 55mph and cross the fence at 60. The vast majority of my landings are wheel (I swear, I’m not trying to pull the scab off of the wheel vs. 3-point argument on a Sunday morning) it’s just what I’m most comfortable with. My dad and brother fly a Swift, and all Swift landings are wheel, I guess that’s just what I grew up with.

Now that my annual is done, I plan to fly up to KCGC and get some real-life turf experience. Their grass strip is about 2600’ with trees on the south side. I’m excited to get some real numbers.

The other issue will be runway orientation. It’ll be a compromise between property layout and the prevailing winds. Thankfully, with easily available Bluetooth-capable weather stations I’ll be able to get a good 6-12 months of wind data.

Thanks again


Since I have opted for six inch wheels when buying my kit I have the option of the standard 6.00-6 tire or even a 7.00, 8.00 or 8.50-6. All those tires would fit the six inch wheel and brake assembly that came with my kit. I own and fly a 1948 Stinson 108-3 and it uses a 7.00-6 as the stock size tire. The plane was designed when most little airports were grass and it handles well on grass. I used an STC to install 8.50-6 main tires on the plane and it is even better!! The more nose high attitude is better for three point landings and the bigger tires roll over uneven surfaces very smoothly. I am kinda thinking I might try 7.00-6 on my 601XLB taildragger but then I think about the extra money and weight and think maybe a 6.00-6 will be plenty for a small plane. We'll see what I decide as the plane gets closer to being flyable.

I currently fly a Cessna 150 with 6.00-6 mains. Empty weight is 1082, with 300lbs of people on-board, I can get it off a turf strip in around 900ft, which is a big increase from the sub 500ft numbers I can do on pavement (hot summer day). I regularly fly in/out of 2500' turf airports with clear approaches on both ends during hot weather. 

The increase in drag on the ground is huge, so popping it up off the ground ASAP and gaining speed in ground effect is the name of the game. (My Cruzer will have 21" mains and 8.00-6 nose to combat the drag on the ground) My real 50-ft distance is closer to 2000', the POH claims it can be done in 1,337 off grass.

When Zenith had their camp out at Lake of the Ozarks last year, I ran the numbers and did a lot of practice runs at a turf field. Mt Eagle Escape is 2100' with trees at both ends of the clearing and the maintenance level of the field was "bumpy" by most accounts. It was a clear no-go for me. 

I would try a few different strips as you will find levels of maintenance varies. 


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