Backpacker makes a good point here.

If you have spats fitted, also check that they are not jammed with grass, as this combined with friction has caused fires in the past.

Good grass runways are delightful (e.g. Fowlmere in the late 90's, ealry 2000's when I lived in the UK), but poor ones are not :\

Having scanned the thread, there is plenty of good advice, enjoy.

Keygrip

IIRC correctly, they do not refer to them as grass runways, which always amused me when asked to sign a declaration that I would not operate the aircraft on 'sod' runways.

I once did try to explain that not all runways that were sods to land on were constructed from grass, but the joke got lost in the translation :}

Grass is OK if smooth; it is what you find in the grass that might be a problem.

Potholes for example. I had a pothole prop strike when new; £20,000.... And the airport washes its hands of liability. So you, the pilot, need to be vigilant. If in any doubt, get out and walk the taxi route - even if there is a queue behind you. They won't be footing your prop strike bill :)

I tend to not do grass in the winter because the plane gets covered in muck, and due to the rut problem below.

Another thing is to get hard parking if possible. A lot of grass runway airfields have a hard parking area. I had to get my plane pulled out (from a rut) with a vehicle more than once, and most fire crews doing this will just do it by the nosewheel :ugh: so ripping off the engine mount. One needs two ropes, pulling on the main wheels.

Otherwise, grass is fine. Taxi with the yoke all the way back to relieve the nosewheel pressure, and do a "soft field" take off whenever possible. I never did those in the JAA PPL; only the FAA one teaches them, it seems.

However, hard runways can be as bad. I know of some (Elstree and Spanhoe being the worst) which are covered in stones, and the users there must be getting a high rate of nicks. These translate into early prop overhauls, or unneccesarily early blade scrappings during scheduled prop overhauls, and that is 4 digits. The technique is to avoid high power slow speed taxi over areas where there are most stones; build up speed before these and then cut the revs. I don't know why somebody doesn't get a broom... at least with grass you don't get this problem.

Having said that, the worst runway I have ever been to was Heywood Farm - a scary experience I am not repeating. Followed by a £200 cleanup job.

That's one hell of a dry-cleaning bill :eek:

Lol@Katamarino

I was taught to perform a short field take off when taking off from grass, which nobody seems to have mentioned. I wonder if it's just me being over cautious. I'm always slightly more nervous taking off from grass than concrete that extra roll is just a little bit more unnerving...

Would endorse those recommendations for nice grass runways - Panshanger, Compton Abbas, Old Sarum all nice (though the latter has quite a hump in the middle - looks alarmingly short when you line up on 08!) and all three have nice cafes, too.

Also recommend Goodwood (Chichester) where your arrival on grass is always greeted by a courteous 'Welcome to Goodwood' over the radio. I've not yet bounced there so I don't know if you get repeated 'Welcome...' for each bounce...

Tim

Paul

Just being grass doesn't mandate a performance take off, IMHO.

What might make the difference when comparing hard and grass is the effect of the factors applied to wet, long (etc) grass, leading one to operate that way.

I flew regularly out of a 700m grass runway and I would run up the engine against the brakes to 2000rpm to see the T&Ps stabilise and use flaps 25 to shorten the ground roll, flying off at around 55, instead of 65. As there were no obstacles ahead, I would trade early lift off for poorer initial climb out.

In principle, on a 700m hard runway, I'd have used flap 0.

The law of the situation applies and I don't think that you are being over cautious, you are still a relatively new PPL taking a conservative view and thinking about what you are doing - that's good airmanship in my view.

Have you seen Safety Sense 7 leaflet form the CAA?

http://www.caa.co.uk/docs/33/ga_srg_07webSSL07.pdf

The performance factors in this book are felt by some experienced pilots (I am not in this experienced category) to be ultra conservative, but they make a good starting point when considering take off and landing performance.

I think you mean a "soft field takeoff"?

A short field takeoff leaves the nosewheel down all the way until Vr and then you climb aggressively at Vx. This is best done on hard runways, but can be done on good grass too. This one is easy.

A soft field takeoff is where you pull the nosewheel up very early in the takeoff run - maybe at 30/40kt in a 60kt-stall-speed plane - and the whole plane floats in ground effect until Vr, then climb away as normal. You don't want too much crosswind when doing this one :) This one needs practice because after the initial aggressive pull-up to get the whole thing into ground effect, you have to increasingly push forward on the yoke, to prevent the plane floating up too high and out of the GE (which will stall it and it will plunge back down).

IO

At the risk of being pedantic, your description of a short field take omits the difference between clearing an obstacle or not.

For the former, the climb at Vx must be maintained until safely clear of the obstacle (having first caclulated that this is feasible), whereas if no obstacle is involved, 50' is a safe height to release the back pressure and start thinking about accelerating to a safe speed/cleaning up (if necessary) and looking for Vy.

Reference is Airplane Flying Handbook - Google Book Search

Not trying to be smart, as I agree with you in the point you are making, just to be absolutely clear for others reading who do not have your considerable experience.

Landing on the hard stuff


Let's see, assuming Scotch has a density of about 0.8 then your average floatplane should be ok - it would float a little lower but bouyancy margins should be OK.

Viscosity is lower than water but which would affect the takeoff run more, lower viscosity, the plane floating lower in the liquid or pilot failing to meet "bottle to throttle" requirements?

So where's this lake full of hard stuff then?:p


I'll just collect my hat:)

...don't forget your coat :rolleyes: :}

All good stuff here and worth noting, but don't get too frightened! Grass isn't scary, just a few different hazards.

To add to a point Backpacker made about lighting and marking, grass runways tend to "look different" on approach. They tend to be all different shapes and sizes, often with the runway not quite so clearly defined as a nice rectangular strip of tarmac. You get fewer cues to being on the right glide path, and when I was learning (and afterwards) I tended to find the first approach at a different grass strip could be a bit ragged. As always: never be too proud or too scared to go around, even from runway height if necessary.

Fredacheck

Interesting point about the visual appearance of grass runways.

This never bothered me, although I can well see how it could be confusing.

My worst optical illusions were (a) the very wide runway at Manston with the hard extnsions that made it nearly wide enough to land on - really b*ggered ujp my depth perception and (b) landing at night on runways with only edge lighting - hello trench!

Also, easier to find a grass strip in winter, when surrounded by brown plouhged fileds, than in summer when they were all green :\

It doesn't tend to bother me now with my MASSIVE 400-500 hours of experience (!) But I can remember it was one of the many things that confused me earlier.
Too true! Fenland is my bete noire. Lots and lots of rectangular runway-sized fields all around.

IO
 

IO

True, I had never seperated out a grass take off from a short field take off, in my mind, but yes you lift the nose up earlier and use ground effect on a grass strip take off.

FREDACheck

For me Middelburg was the worst field to spot from GoogleEarth http://maps.google.co.uk/maps?hl=en&ie=UTF8&ll=51.515233,3.714366&spn=0.041662,0.1112 37&t=k&z=14. Didn't make it out there last year due to fog, but hopefully this year...

FREDACheck

Well you have a bit more experience than me!

But, even at low hours, I never even noticed the things you mentioned, so I wonder if it is more of a physiological thing? i.e. the way our individual eyes and brain are wired.

I've always tended to land a foot/18" left of the centreline and even in a flight sim with a TRE from a major airline observing, I did the same repeatedly and he couldn't see any tangible reason for it :\, just saying it wasn't dangerous and it was consistent (they lilke consistency.)

I do agree about Fenland though, even with VOR and GPS, you could be nearly overhead and still not spot it!

Paul

Not being pedantic, but IO said 'soft field.'

This could include other surfaces such as sand, but not include firm grass.

An important difference when considering take off performance and the best technique to use, for instance whether to use a rolling take off or run up against the brakes on a short strip.

No, Middelburg (actually called Midden-Zeeland, EHMZ) is easy. Just ignore the field altogether and look for the point where you join downwind. You need to join from the North in any case, so follow the "Veerse Meer" lake until almost its southernmost point (actually the little harbor just NE of the southernmost point), head due East or West at 700 ft, look left or right as appropriate and hey presto, there's the field.

But in general, yes, it helps to use Google Earth to spot a few useful landmarks to find the entry point in the circuit, in addition to the runway itself.

F3G - indeed. There is no reason ever to climb at Vx, except to clear an obstacle, or to impress the spotters :)

Sand ?!
 

Ouch has anybody actually done that ? Doesn't it positively spew sand all over the place ? :eek: