Operate from 450 feet of grass?

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Georden

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How about a gyro, strapped down to a base, a splined shaft (like a PTO shaft) connects the base to the rotor and an external engine drives the rotor above flight rpm, the straps keeping it on the ground. Apply full power, release the straps and hopefully jump high enough to reach flying speed before coming back down. Kind of like those pull string helicopter toys.
 

Georden

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If you are going to add collective control to a gyro why not just add a tail rotor and have and helicopter?

Edit: now you got me thinking. What about kaman style servo flaps, used to twist the blade to a zero/low lift state. Might be able to make it simpler than a conventional swash plate.
 
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cluttonfred

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TFF

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An Aircam doesn’t have to do the zoom climb. Essentially the same type of plane with another 100 hp. Still pretty tight once you leave the ground. Rotation for that Dragonfly was around 250-300 ft and another 300 before the climb. It is totally impressive performance. Still Short of 450. You need something on rotation that can go into a 30 degree climb right away. I had a friend with about 1100 ft runway. His house on one end, another property’s trees on the other. There was a hole next to the trees that had even more imposing obstacle,TVA power lines. He could get his Champ out of there solo. Takeoff was the issue with that plane. It would just barely clear. His Jungmann had no problem with takeoff but landing was a nail biter. Skip Stewart did it three times, my friend was never brave enough and he had 20,000 hours +.
 

reo12

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I started out flying Pterodactyl's. I actually used a field I owned that was rising terrain from the road - to a wall of trees. The elevation went up about 10ft at the tree line. There were power lines at the road. Total distance from the road to the trees - about 280ft. Takeoff was done by backing the plane against the trees and launching down hill - and climbing out over the power lines. Landings were reversed. Approach at just above stall speed with all kinds of wear on my shoes for braking before ending up in the trees.
One morning I took off and there were minor winds aloft. I realized that they were picking up as the sun warmed the ground so quickly returned to home. On approach I was having issues with wind gusts so went around. On my second attempt - the wind speed dropped just as I was about 15ft off the ground. The wing stalled at about 10ft agl. I damaged the hang tubes and the canard - broke the nose gear. Bruised my legs a bit. I was very thankful that I was wearing leather high top work shoes as I believed they protected my ankles.
I repaired the plane and flew it out of the field. I have never considered flying into the field again.
What the performance numbers say what a plane can do - and what the pilot can make the plane do when conditions are less than perfect are totally different situations.
 

Skypilot053

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Typically distance to clear a 50 ft obstical is 2 to 2.5 times the takeoff roll and that is on low density altitude days cut down trees at both ends 100 ft wide sell the lumber
 

Georden

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Typically distance to clear a 50 ft obstical is 2 to 2.5 times the takeoff roll and that is on low density altitude days cut down trees at both ends 100 ft wide sell the lumber
If I clear right to the property line I get another 100 feet before hitting trees that aren't mine. If 450' isn't practical I'm guessing 550 still doesn't leave much safety margin.
 

Rhino

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It would in a Zenith, but I suppose that depends on how you define "practical". That is well within the specs of the 701 and 750 STOL models, and probably the Super Duty (haven't checked). Some owners of such aircraft routinely operate from such spaces, many of them even smaller. There's been a lot of focus on takeoff distance here, as is the norm for such discussions. But landing roll is longer than takeoff roll, so don't forget to take that into account. I wouldn't consider such operations until I had a pretty good experience level in STOL operations, but would have no qualms about it after that. Just remember to practice good risk management, and take into account that limiting factors, like crosswinds and density altitude, will be multiplied when doing this. Some pilots get experience with STOL ops, but forget that some 'normal' risk factors can be significantly higher in such circumstances. In short, I would have no problem doing what you envision with my 750, as long as I'm careful not to become complacent or overconfident, and as long as I'm totally comfortable diverting elsewhere anytime conditions and circumstances make that advisable.
 

qchen98

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What about a zenith with two pod-mounted PBS-TJ100? They only weight 43lbs each.

You'll get 400 lbs of additional thrust on take-offs and a potential increase in payloads.

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Dana

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A few years the owner of Goodspeed Airport near me (42B) wanted some trees down near the end of the runway, they had been lower but had grown up over the years. Problem was, they were on state land. He cut them down anyway, cleared a path all the way to the river. Most people figured the fine he paid to the state was less than the cost of getting permission to do it legally, and they couldn't put them back.

Probably not the route you want to take, though...
 

qchen98

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Get an Agent Orange STC for the Zenith and go after the tress.
 
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BJC

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The STOL 750LS POH is here http://www.zenithair.com/stolch750/data/Draft POH STOL CH 750-SLSA June 2009.pdf

The data in the POH, with an O-200, doesn’t support the claim that it is capable of meeting the OP’s desired performance.

Note the increases for taking off from grass. Note the increases for typical summer day temperature. Then factor in less than perfect piloting, engine performance, etc.


BJC
 
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Rhino

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The STOL 750LS POH is here http://www.zenithair.com/stolch750/data/Draft POH STOL CH 750-SLSA June 2009.pdf

The data in the POH, with an O-200, doesn’t support the claim that it is capable of meeting the OP’s desired performance.

Note the increases for taking off from grass. Note the increases for typical summer day temperature. Then factor in less than perfect piloting, engine performance, etc.
The performance specs do support it.


And the other stuff is what I was talking about with risk factors being far more important when pushing the envelope like this. To quote Clint Eastwood, "A man's got to know his limitations."
 

Rhino

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Thanks for the POH by the way. I didn't have a copy of that one yet. Trying to customize one for the Jabiru 3300.
 

BJC

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The performance specs do support it.
POH says 744 feet to takeoff and clear 50 feet at std temp, 840 feet at summertime temperature, zero wind.

Landing over 50 feet, 560 at std temp, 620 at summertime temp, no wind.


BJC
 

Rhino

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I'm sure it does. I'm also sure, as I'm betting you are as well, that many, many aircraft routinely outperform book numbers, and in many circumstances do it on a daily basis without incurring undue accident rates. Many aircraft also underperform their POH numbers. Zenith STOL aircraft routinely perform exactly the kind of operations being discussed here, all over the world. We all know safety is a relative term. Nothing is 100% safe, especially so in aviation. We gauge the safety of our operations by acceptable risk, experience and common practice. Any STOL operation involves more risk than landing on a 10,000 foot concrete runway in no wind on a cool, sunny day. But we almost never get those circumstances. So we weigh our operations risk based on the hand that's dealt us. If what I said was something unusual or unheard of, then absolutely it should be viewed very skeptically. But it isn't unusual at all. STOL aircraft, Zenith and many others, perform such operations on a daily basis all over the world. Is it the most common practice? No. Is it the safest way to operate an aircraft? Absolutely not. Technically the safest aircraft operation is to never get in the aircraft at all. But can it be done relatively safely? Absolutely. But again, the relativity of that safety depends on many factors, and is always subject to our own comfort level. This situation most definitely calls for the highest levels of scrutiny and care, but it isn't uncommon and can be done safely. That doesn't mean anybody can do it, in any aircraft, nor even remotely does it suggest they should try. But if the pilot involved is willing to go the extra mile to gain the requisite knowledge and experience, and be far more careful of conditions than would normally be the case, there's no reason why they couldn't perform operations like this that are routinely performed by others, in the same aircraft. How many STOL operations have you seen or heard about being performed that fit within the published parameters of a POH? I'm betting almost none. There'd be a whole lot less flights if we actually believed POH numbers were always set in stone under all circumstances. Probably be a whole lot less pilots too. I'm in no way advocating the OP engage in any unsafe activity or in any activity he's uncomfortable with as far as safety's concerned. All I'm saying is that it is possible to do this under the right circumstances when the proper precautions and preparedness are observed.
 

Dillpickle

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The pilot held that on the
An Aircam doesn’t have to do the zoom climb. Essentially the same type of plane with another 100 hp. Still pretty tight once you leave the ground. Rotation for that Dragonfly was around 250-300 ft and another 300 before the climb. It is totally impressive performance. Still Short of 450. You need something on rotation that can go into a 30 degree climb right away. I had a friend with about 1100 ft runway. His house on one end, another property’s trees on the other. There was a hole next to the trees that had even more imposing obstacle,TVA power lines. He could get his Champ out of there solo. Takeoff was the issue with that plane. It would just barely clear. His Jungmann had no problem with takeoff but landing was a nail biter. Skip Stewart did it three times, my friend was never brave enough and he had 20,000 hours +.
Ground to build speed and zoom. Try this one for a real takeoff.


I've flown Two stroke and four stroke Dragonflys, and both will do this. They will also do spins, flat spins, loops, and snap rolls.
 
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