I am considering construction of a landing strip on some property I own for use with an Aeronca Chief, a
Taylorcraft BC-12D or similar and am seeking input from individuals who have undertaken such a project.
Hoping ,of course, that their knowledge and experience will help me with my effort. An immediate problem arises from the fact that the maximum length will be about 1000 feet and that Powerline obstacles (50 feet) exist at the ends of the 1000 foot segment. I am aware of the nominal considerations for short field use and the impact of weather variables etc. I am seeking the thoughts of pilots who have
operating experience in similar scenarios and/or have constructed airstrips like this. Thank you.

Power lines at each end I think it is kind of short. Be easier to land than take off. Grass will act as brakes for landing and taking off. I think that if the lines were realy 50 above ground with no phone wires below that and no fences, I would consider coming in below the lines. If they are at 30 to 35 feet like arround here with a phone line below that then I would not do it.

My grass is 2300 ft with a fence at each end so if you take off 150 ft at each end fore displaced threshold, that give me 2000 ft at 2640 ft MSL. With 4" grass, fully loaded 182 I am about 5 ft AGL at the half way point. But the engine is a bit tired.

Tim

maximum length will be about 1000 feet and that Powerline obstacles (50 feet) exist at the ends of the 1000 foot segment.

That's cutting it close!!
My strip is 1000' with 40' trees at about the 1,200' mark & I get in and out fine with 1/2 gas & two people with both 65hp Chief & 65hp Taylorcraft, I am however in cooler climates than you likely have.
I'm thinkin a hot still day & you might be pushing the envelope, as above would be if you had the option to sneek under the wires if necessary.

Edgefly, I have built a longer strip with an obstacle on one end, but not to the degree you mention. If the power line you mentioned is not a major supply line (towers) then it may be possible (for a cost) to get them to bury them for the short distance required. I did have an experience where the power company worked with me, on a somewhat similar, non-aviation situation, but it cost. If the power line is one of the high ones and remains in place, that location does not seem like a good option.

Steve

My strip is 2200ft north and south with 50ft trees on the south end. When I put the grass in, I also put in a 1000ft strip east and west off the north end. 250ft off the east end are two power lines, one on each side of the road. So that is a 1000ft grass strip with power lines 250ft off the east end. The power lines are 30ft high.

Stock cessna 170B, 1280lb empty weight, all weather and wind variables considered only one problem continued to arise. The power line on my side of the road was hard to see landing. On take off that line was always visible but on landing it would blend into the field.

I considered having the orange markers put on the line, but instead I took the strip out. It no longer exists. Power lines are just unforgiving. Look for another option or a local airport.

Are we talking high voltage pylons or local distribution 'less high' voltage?

There may be an option to have the lines buried between two poles, if its not HV, that was done at one of our local airstrips and the comfort factor is great! It makes for a much safer approach, now there's just the deer fence to catch you

Obviously its not a cheap fix, but what about aviation is cheap... and can you price safety, yacka-yacka you know the tune.

How did they get them down from there.....?!

Years ago when I was chairing the Laramie airport board, we tried to persuade Pacific Power to bury the power lines which were paralleling the highway to the northeast of the approach to 21. We had had several airplanes over the years strike the wires--one I recall was a Baron which lost the top of its tail! The cost was outrageous, measured in millions. We did finally persuade them to install the orange balls, at airport expense.

Landing on a 1000' strip with 50s at both ends means that the strip is effectively a lot shorter. Even a relatively steep approach angle--say 6-8 degrees, will put you a few hundred feet down from the end at touchdown, because you'll want to be several feet above the lines--not too neat to get a sinker at the wrong moment. That means that every approach, every landing, has to be nearly picture perfect.

Take offs are even more problematic. Whenever density altitude is a factor, you want at least one departure direction with no obstructions. 50 footers on both ends would really make me have second thoughts about taking off at all. 100 footers, I can fly under, but 50 footers is cutting it too close for my comfort. And as invisible as wires can be, I'd like to have the balls added for visibility.

I kept my LRB (P172D, 180hp Lycoming, CS prop, semi-stol equipped) at a grass/gravel/dirt strip between Wellington and Nunn, CO for a year, which is at 5300' MSL and 2800' long, with a 40' power line on the northwest end. There's a slight downhill run to the southeast. Today we had a fly-in there (annual Memorial Day affair), and watching everyone take off and then taking off last myself, I was glad for the lack of obstructions on the southeast end. DA was about 7500'. I broke ground at about the half way mark, with 2 adults and 2 kids, and still about 3 hours of fuel aboard, well within the traditional 70% by half way, but climb rate was nothing to be proud of.

Cary

For a rough calculation the takeoff and landing rolls are about 40% of the distance to clear a 50' obstacle from a level, hard surface with no wind. In legalese they really mean using every inch of pavement and a theoretical obstacle. I'm sure you don't want to clear your real obstacle by 1/2". Unless I missed it you don't say what altitude you are at but in any case I'm with the crowd here, it doesn't sound like you have enough unless you want to trade for a helicopter. sorry, it's a nice dream to have.

porterjet wrote:For a rough calculation the takeoff and landing rolls are about 40% of the distance to clear a 50' obstacle from a level, hard surface with no wind.

Hey John I don't get it. Can you help a old slow pilot here. I ask because I am working on landing my hay field. 1200' to 50' trees. But it is down hill take off.

G'Day...Rob

Hey Rob, what I meant was if the book says it takes 1000' to clear the proverbial 50' obstacle then 400 of that is the actual takeoff roll, probably more on a grass runway. Using Lucia Mar Unified school district math that means it takes 600' to climb that first 50'. That is not much of a climb gradient since you are also accelerating to Vx and on some airplanes still have the flaps hanging out. That 40 % is rough of course depending on the airplane. Downhill rolls help since you accelerate faster but they also increase the accelerate-stop distance to the point where large part 25 aircraft are certified with a 2% slope limit. (up or downhill).
Also not shown in most light aircraft operating handbooks but derived from reading large airplane numbers is the effect of wind. Lets say, off the top of my head, that a 5 knot headwind lessens the takeoff distance by 4%. However a 5 knot tailwind might extend the distance by 6%. A tailwind is worse than a headwind in every flight manual I have looked at.

In your case landing uphill over 50' wires, IMHO, is not nearly as scary as taking off over them in a 65hp T-craft. The 200' difference in length between your two strips might make all the difference.

What I was really trying to do was get everybody to think about the obstacle and how much margin do you want in real life.

That got kinda long winded didn't it.....

edit: Clearing an 8' obstacle by 42' is a hell of a lot different than clearing a 42' obstacle by 8'.

Thanks PJ. I got it now.

Today departing Pacific City. 30 gallons of mogas. Pilot 175lbs Right seat 225lbs, another 30lbs of misc crap. Sea level, 5kt head wind. At 1000' from the start 100AGL at 1875' from start 250AGL

G'Day

Don't do it. Not all days are perfect, unless you can go under like someone mentioned.

OregonMaule wrote:Today departing Pacific City. 30 gallons of mogas. Pilot 175lbs Right seat 225lbs, another 30lbs of misc crap. Sea level, 5kt head wind. At 1000' from the start 100AGL at 1875' from start 250AGL.

And that's with what, 235 horsepower? Far cry from 65.

My strip at home is 1200ft with 50 foot wires at both ends - not ideal as a home base but I have another couple airfields handy to call on when conditions are marginal at home. Generally landing with reasonable weight is OK but no matter what the paperwork says, those wires on departure always have me on edge and I fly out of this strip pretty light. If you have options for handy strips on bad weather days that's all good, but as a home base it may be tempting to push it to land back home and come unstuck!

OregonMaule wrote:Hey John I don't get it. Can you help a old slow pilot here. I ask because I am working on landing my hay field. 1200' to 50' trees. But it is down hill take off.

G'Day...Rob

Down slope 50' trees are shorter than upslope 50' trees because of the upslope itself becoming an additional obstacle beyond tree height. A down slope tree might not be an obstacle at all when measured from level at the point of takeoff.

dirtstrip wrote:

OregonMaule wrote:Hey John I don't get it. Can you help a old slow pilot here. I ask because I am working on landing my hay field. 1200' to 50' trees. But it is down hill take off.

G'Day...Rob

Down slope 50' trees are shorter than upslope 50' trees because of the upslope itself becoming an additional obstacle beyond tree height. A down slope tree might not be an obstacle at all when measured from level at the point of takeoff.

Yep the slope has been taken into account. Hand held WAAS GPS, google earth, 100' tape measure, and now my measuring wheel have been in use. I am amazed how accurate google earth is when you measure. The trees are much taller than 50' but the effective height is real close to 50' I'll get the lazer transit out for some better height info.

The take off altitudes I mentioned were just for comparison.

So EDGEFLY, when you takeoff from a field at the same elevation as your field, no wind, operating weight, and a temperature you will operate at what is your AGL number at 1000' from the start? Also the height of the grass makes a huge difference too.

G'Day...Rob

OregonMaule wrote: Today departing Pacific City. 30 gallons of mogas. Pilot 175lbs Right seat 225lbs, another 30lbs of misc crap. Sea level, 5kt head wind. At 1000' from the start 100AGL at 1875' from start 250AGL

Curious how you captured those numbers. I tried doing that yesterday and realized there's a lag in both my GPS & my altimeter. Not a huge lag, but enough to where I woudn't want to try to depend on them for anything close.

Oregon Maule,
I don't have typical aircraft ( Chief or BC-12D) available at the moment, so I don't have the number you are looking for to give you. I will be making a summary response tomorrow which may give you some further insight into my planning. Your inflight data at Pacific City is interesting. What aircraft and weather conditions apply to it. ?