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-   -   One way strip Five degree slope (https://www.pprune.org/pacific-general-aviation-questions/549999-one-way-strip-five-degree-slope.html)

Sunfish 25th Oct 2014 08:38

One way strip Five degree slope
 
Looking at a property with potentially space for a one way strip with a Five degree slope for a STOL aircraft (savannah). Nice approach landing uphill, takeoff downhill.

The alternative is a couple of short flat locations with curved approaches to avoid river red gums.

thoughts?

rutan around 25th Oct 2014 08:56

Sunny,
On the one way strip can you do a go around from close to the ground if you stuff up the approach?

Squawk7700 25th Oct 2014 09:01

Give us a google maps reference and I'll see if I can get in there for you. I can get down in 300 metres or less

You'd better let the owners know of my impending "approach" as I don't want another one of those phone calls and letters from CASA, something about "show cause." (Seriously). Those model aeroplane "pilots" weren't expecting a "full size" to drop in...

Ultralights 25th Oct 2014 09:13

A savannah you say? all you need is 100 mtrs...

Capt Fathom 25th Oct 2014 09:31

Thoughts?

Without seeing the proposed "areas of operation", how could anyone possibly provide any useful insights??

Jabawocky 25th Oct 2014 09:34

Curved approaches are easy, it is the curved….err bent like a boomerang strips that keep your eyes wide open. Especially in slicker machines than a Savvy.

I have done both the boomerang strip and the one UL might know up here, and I would say any are fine if treated with respect and you set standards. The hardest part is knowing when to bug out. That is how you avoid bent machines and such.

Be careful down there! :ok:

Squawk7700 25th Oct 2014 09:38

Jaba if you have the link can you post the YouTube of UL's Savvy on that "tight" strip? (With "tight" being an understatement)

chimbu warrior 25th Oct 2014 09:49


Five degree slope
5 degrees or 5 percent? 5 percent is pretty straight forward, 5 degrees is a bit more challenging.

Squawk7700 25th Oct 2014 10:24




Ultralights 25th Oct 2014 11:18

headwinds are cheating! no wind here..



how about a real tight strip...


ForkTailedDrKiller 25th Oct 2014 11:52

Wanna aeroplane (appear to) fly backwards?

Just pass a Savannah in a Bo!

Strainer 25th Oct 2014 12:18


Wanna an aeroplane (appear to) fly backwards?

Just pass a Savannah in a Bo!
....or a 172.

spinex 25th Oct 2014 22:13

Jabawocky, how long is the strip in your video? I'm sure there is some foreshortening thanks to the camera lens, but that's not just short, but pretty much hemmed in by trees too!

ranmar850 25th Oct 2014 22:33

How much headwind was there in the first Savannah clip? it appears more levitation than aviation :ooh: I mean, you could do something similar with full flaps in a C172 into 50 kts of headwind, but I don't think I'd want to be in the air with that kind of weather.

And as per spinex's comment, no room for error there--what could the windshear possibility be when you got below the level of those treetops? Can't imagine more than a breath of wind intruding at strip level amongst that cover.

uncle8 26th Oct 2014 04:28

PM sent
 
PM sent...................

Flying Binghi 26th Oct 2014 05:07

"thoughts?..."..:ooh:


My 10c... If yer gotta ask the question - DON'T.

Get a fellow Savannah owner familiar with operating to the type of strip(s) you intend to build to have a fly around and access it for ya..:ok:











.

HarleyD 26th Oct 2014 06:15

FB has hit the nail on the head there.

If you are not familiar with the techniques for one way strips it's best to get some training/ guidance from an experienced pilot.

The issues associated with one way strips are numerous and nog always obvious to the uninitiated.

Tail wind on landing is often the main reason to prevent usage. There is no point launching in to a stiff headwind if you can't get back on.

Uphill tail winds create quite strong reverse wind shear and the wind is going uphill trying to lift the plane up with it.

Go around point may be well short of touchdown and once past this point you are committed like it or not, again the tail wind will significantly reduce climb in two ways by decreasing climb angle, GS/RoC, and the reversed wind shear will tend to decrease airspeed with increasing height during initial climb.

I have flown 2 and a half ton aircraft from 300m one way strips, so a savannah should be straight forward, but it is the unknown unknowns that can bring those new to one way hill strips undone, and I have seen it. In PNG I have flown into hill (mountains really) strips where the go around point was 500 metres from the strip which is still out of sight around a bend in the blind valley. These abort points are learned from the lessons of others, so you just use that advice and don't improvise. If you are arent on slope on speed at your go around point GO AROUND right away. Too high/ fast is just as bad as too slow/ low.

Go around is often to turn away down an escape route with descending terrain rather than a straight climb.

A sloping strip at the top of a steep bluff can also provide a vertical lift impulse right at flare which can increase speed and displace the aircraft significantly into the strip. Anticipating such a vertical by deliberately approaching low and slow is fine if it all goes as anticipated, otherwise you end up low and slow under profile and short of the strip on the wrong side of the drag curve. I have seen it.

Get a specialist with some type of industry experience, not a self taught 'expert' with limited knowledge of the traps. An aggie or ex aggie or an ex MAF or PNG pilot. They will identify hazards and assist you to put a little bag of tricks together to get you out of jail when conditions and micro climate make things difficult.

HD

My auto correct keeps trying to turn aggie into aggrieved. Maybe it's onto something.

Ultralights 26th Oct 2014 08:16

the savannah around Bankstown now is affectionately know as The elevator...

there was a day of 20 kt winds right down 11.. was a fun day. good for a giggle when the tower ask to confirm you are moving forward... :}

Jabawocky 26th Oct 2014 10:27

Spinex…they are good for a 50/50/50/50 circuit, :E and there are some shorter strips than the one in the video, but not for the inexperienced.

but you need to find a nice paddock or sand bar for that. :}

I have beaten both those guys in a short field comp in one of their savvy's……but I must say it was a lucky break….i do not claim to have the skills others do….coz I don't!


UL……you are a classic guy! Going forward :D:}

compressor stall 26th Oct 2014 11:02

Sunfish,

Swifts creek?


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