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Max
15-03-12, 20:33 PM
Looking to speak to the local farmer about the possibility of a strip, and would like to know what sort of length would be ok?

Mine has a 462 HP, if anyone has any real life performance figures, take off + landing roll, + to 15m at MTOW would be most helpful, am thinking around 300m, but the location I am thinking has 300m available, clear approach one end, and then a telegraph wire at the other....

Any info greatly received!

Max

Terry Viner
15-03-12, 23:02 PM
Have you not thought about getting some short field flying under your belt first Max, it would help you make field assesments a lot easier for you.

TV

jjones
15-03-12, 23:32 PM
Mine has a 462 HP!

Max

anything over 10m would be sufficient for take off :D

Katie
15-03-12, 23:34 PM
I thought you flex wing guys went straight up and down :) but yes, there are text book numbers and there is what you are comfortable with, 2 different things to most pilots.
Also what will work on a cool day with a headwind will not work on a hot calm day, remember the numbers in the book are based on ISA. Leaning how to read the weather is very important with short strips, landing anywhere is easy with the right wind direction/strength :)

Max
15-03-12, 23:57 PM
Thanks all, the 462HP, its VSTOL ;), I meant the 462 with the hi-power exhaust :)

Text book numbers are 150m for T/o and 230m for landing at MAUW to/from 15m, the field has over 800m available, it's just being sensible with the amount needed, obviously will be different from the 6-1300m i'm used to at Half Penny, which allows us to Take off, land and take off again in the Quantum at MTOW.

I personally think that between 350-400m would be suitable, just want to get some real world figures on the Flash 2a :)

Max

Gentreau
16-03-12, 02:56 AM
The text book numbers are those demonstrated by a test pilot after lots of practice. Can you match them on a regular basis ?
The normal guidance (if I remember rightly) is that your required runway length should not exceed 70% of the runway length available.
That would put your required length at 330m for landing.

Another thing to consider is that even if you are comfortable with a certain runway length, if you want anyone to visit you, they may not be able to if the strip is too short or difficult.
Personally, I would have thought that 450m would be a good bet, allowing for slightly long, high or fast approaches.

ANDY1973
16-03-12, 08:08 AM
Clive's numbers sound pretty good to me.

You need to be very honest with yourself, and think about the runway distance that you need on your worst landing on the worst weather conditions that you will fly in. Its great if you can replicate the text book answers and match the company test pilot's performance on 95% of your landings. But if you have a floater every once in a while, and the grass is a bit slippy, and it's a nice, hot, calm day; then you could find yourself embarrassed.

As we all know from the initial stages of learning to fly, the difficult thing about landing is achieving consistency. Gaining experience after finishing your instruction certainly helps your consistency, but maintaining regular flying currency is also a huge element in this. Even with a fair few hours behind me now, I know that after a few weeks off flying my landings are not as accurate or consistent as when I'm flying regularly, and I would not consider a landing to a shorter field until I'd got back into practise.

A

Bob T
16-03-12, 11:03 AM
It all comes with experience. Short strips can be very daunting when you are a low hours pilot. I practices in a Quantum and a Raven on the short taxiways at RAF Wyton when I started flying, my instructor made me do it. Now (17 years on) with a machine that can fly nice and slowly, I think nothing of dropping into a 120 meter strip.

paultheparaglider
16-03-12, 11:04 AM
Max,

A lot depends on the entry and exits to your strip, and any obstructions such as buildings, trees, or anything likely to cause a rotor of some sort. Also, if you don't use the full 800m available - presumably because the rest will be in crop - I'd be careful with what the crop was if you overrun into it or have an EFATO. Weight will play a big part in your decision as it makes a big difference to short field performance with most older trikes. If you regularly operate at high weights then go for longer.

Longer will always be better, but I would have thought 400m would be fine. Especially if you cut it as far from that wire you mention as possible. However, to operate safely from a short strip you really need to develop the mindset that you will go around at the slightest sign of the approach being anything other than perfect. This is probably the critical point. And, if you don't think you can do it safely after a couple of attempts then go and land elsewhere.

I operate a Blade 912 out of 200m with fairly good approaches, and I find it quite challenging to do so on a regular basis. When conditions are perfect, it isn't too bad, but conditions are rarely perfect. My strip has all sorts of tree obstructions all around, and sits in a valley where winds tend to be light but can regularly have a crosswind component. Thinking about the landing as I fly back to base on gusty and thermic days can be stressful, even for someone who has been flying a long time. I'd give a lot to have an extra few hundred metres available to me on those days. What I do have is an agreement with a nearby strip that I can divert there if I just can't get down happily at my place. My biggest fear is an EFATO, and you need to have a plan for this. For me, 300m with a wire at one end would be more worrying than 200m without because of what you have to deal with with an EFATO.

Perhaps you could cut 400m at normal width, and have a narrower section for the remaining 400m? That would be a good compromise between safety and having as much of the land utilised for crop as possible.

For sure, don't cut a short strip and then initially go on to practise there. Practise at a longer strip which you have marked out at the length you intend to cut at your place. And then if you have any landing at all that isn't within your own strip length then treat that as a balled up trike with possibly a balled up Max and passenger. You have to be able to do it with a good safety margin 100% of the time. 99.9% isn't good enough.

Gentreau's point about visitors is a good one and worth considering too.

So go to a nice long strip. Get some practise at MTOW and with a tape measure, and hopefully you will be in a position to answer your own question.

Paul

NigelJ
16-03-12, 12:24 PM
The long strip at Redlands is 700m and that is ample for landing, powering up and taking off again with plenty of spare room, even 2-up (and neither of us are exactly small...). The shorter one is 320m and is ample for a 2-up take-off and landing but I don't think I would be comfortable going straight up again.

Roger Mole
16-03-12, 13:06 PM
The winter runway at Linton is under 250 yards and Paul Leigh coped with that quite easily in a Quik. With respect I think I'd turn it round and suggest that if you have to ask the question, you're not really ready to be flying from a short grass strip so if I were you I'd leave it for a year and get some hours under your belt first.

MadamBreakneck
16-03-12, 13:18 PM
Some good tips above. As you may guess, this isn't the first time someone has asked this question. As ever, the BMAA has some useful published information.

Appendix B of this document has some recommended minimum criteria (recommended, chaps, not mandatory - calm down!) for microlight sites:
http://www.bmaa.org/upload/U215788_code_of_good_practice.pdf

There's also a good screed on understanding the performance of your aircraft and the effects of things like slope, grass, temperature etc on your take-off and landing distances in this Technical Information leaflet:
http://www.bmaa.org/files/til006_1_understanding_performance_data.pdf

From my own experience at Saxon Microlights old site at Sheecoates Farm (http://tinyurl.com/56rcuo), you may want to give yourself a suitable length of runway but allow also for some longer grass at each end as overshoot and undershoot buffer zones.

Joan

Max
18-03-12, 19:11 PM
Thanks for all the info guys :)


Max

Mick_Sanderson
19-03-12, 19:53 PM
260m is adaquate, we have runway 10/28 with 2meter fence on the 28 threshold & 2meter hedge on 10, comming in at a airspeed of 60mph+ no need for any or very little braking. GT450

La Goele
19-03-12, 20:22 PM
Most of french ultralights strips are between 250 and 400 meters long (minimum required is 150)
but the length problem is mainly for 3 axis, for weighshift, 200 m is fine, 300 is very confortable
(as far as there is no obstacle in the axis of the strip)

dave nixon
19-03-12, 21:08 PM
300is loads Max 2 mates came and landed here full load and they took off down wind so plenty[mines 300],they were in a 462s/c rapier.

damienair
24-03-12, 01:30 AM
Fully agree with the above. 300 metres is loads, I was operating my Pegasus XL 462 out of a strip which was 300 metres, electric power cables on the numbers at one end and a 20 foot high ditch on the other. It was tricky in the Skyranger but an absolute breeze in the XL and I am a low hour Weightshift pilot. I now have my XL in a new strip fully rigged, runway lenght 180 metres, it's very tight but manageable. Blade 582 and a Pegasus XL 462 operating out of there. 300 metres should be fine, but always be ready for a go around unless your bang on.

dave nixon
24-03-12, 07:24 AM
I think Damiens last comment about being spot on with getting down on the mark is very important and to practice on larger strips at a marker [road cone] gets you use to landing on a specific point no sloppy landing allthough at the left end of my strip there is a very large muck heap ,nice soft warm escape if not stopping to well :laundry: