View Full Version : runway wet

26th Oct 2007, 12:41
I tried hard to find it out in my papers but i didn't...does anyone of you remember if, concerning runway surface condition, it has to be reported by competent ATC unit or Atis or if it is a pilot assesment?

26th Oct 2007, 13:35
No way for pilots to asses rwy conditions.As I remember, a pilot may confirm if FC/BA are real.
FC friction coefficient
BA braking action

26th Oct 2007, 18:58
My understanding is :

Runways are wet or dry (damp on a grooved surface means dry).

Pilots may decide a dry runway is wet, but may NOT decide a wet runway is dry (this might be a company ruling rather than an authority one)

26th Oct 2007, 21:57
my question is:
legally speaking, have i to refer to ATC or Airport authority assesment or as soon as i see that the surface appears "reflective" have i to consider it as wet?
Hardly ever, in Italy, even after a thunderstorm or after a heavy rain on the field, you can get a runway condition wet reported on Atis or Atc comunication....what happen in other countries?

old,not bold
27th Oct 2007, 10:44
A telephone conversation some years ago:

Concorde Fleet Captain; "We won't land if the runway's wet."

Airport Managerial Person: "What, precisely, do you mean by wet, since I'll be making the call, it's an asphalt runway, no grooves or anything, and a little under 2000m LDA as you know, and I won't even mention the state of the stopway".

CFC: "Oh, you know, wet."

AMP: "Give me a bit more, I'm not a Concorde pilot".

CFC: "Well, if you insist, for us on that runway wet means any visible moisture at any point on the surface, no matter how little".

It's horses for courses, really.

B737 lover
27th Oct 2007, 15:39
I think the best scenario here is whenever in doubt, just go for wet afterall you are better off with wet instead of dry and there is nothing harmful to it.

27th Oct 2007, 17:10
yes i agree with you 737lover but i was wondering about Legal point of wiew...

29th Oct 2007, 06:01
The thing of considering it wet when it is not, is that you'll be limiting your mtow (in some cases) and that might be unappropiate...

I get your point L'argonauta, If you happen to reject a take off and over run, who will pay for the damage??

Well, as far as i am concerned, if the tower / atis says it's wet, i'll consider it wet... If they say it's dry and i see it looks shiny, I'll consider it wet... If they don't give the information, I ask for it a thousand times if necesary...

For landing, I'll get that info from the tower and if im in doubt, i'll contact the company frequency, even though they don't take responsability for the information they gave to me, I think i can pretty much rely on it... IF there has been a thunderstom as you say, i'll tend to think it might be wet...

Anyway, in terms of legal responsability, i think that it's part of the air traffic service responsability to asess the friction coeficient of the rwy surface... It's them who have the mumeters and all...

Ciao, spero di essere stato utile!

29th Oct 2007, 10:34
molto utile amico mio! thanx a lot!:):):)

29th Oct 2007, 10:40
ATIS (in the UK anyway) can be up to 1/2 hour out of date. Runways dry out in much less time than that. Takeoff - pilot assessment, landing - ask for latest state. JAR-OPS definition of wet is if sufficient moisture is present to form a surface film or if surface appears reflective. Grooved or porous runway surfaces may be treated as dry unless so much rain has fallen that a surface film is present. Probably.

good egg
29th Oct 2007, 18:14
In the UK the prescence or otherwise of surface water on a runway is to be reported on the RTF and ATIS.In the UK WET is defined as "The surface is soaked but no significant patches of standing water are visible"(Standing water is considered to exist when water on the runway surface is deeper than 3mm. Patches of standing water covering more than 25% of the assessed area will be reported as WATER PATCHES)Hope that helps

30th Oct 2007, 20:38
Hoping to help.....As far as I know (Certainly at mine) major UK airports report runway surface conditions after an inspection by a member of Airfield Operations. The inspection is done on any change to weather conditions. A runway may be called wet from dry when it is obvious i.e in a heavy rain shower. but cannot be called dry from wet without the inspection.
ATC or an A/C Commander may request a runway inspection should there be any doubt. Damp is only called on discolouration of the service due to moisture. We have a grooved runway and call the runway wet if any moisture is present even in the grooves.
Some days it is hard to decide between damp and wet. On those occasions we would err on the side of caution and call wet.
We usually get to call the change from dry to wet within minutes and the ATIS is changed when we inform ATC. Changes from wet to dry take a bit longer on occasions as the runway can dry fairly rapidly in some instances. i.e a good wind. Once the rain stops we do try to inspect regularly to try and catch it ASAP,
It's a bit of a pain when a passing shower gives us a Wet, Damp, Dry call or Damp, Damp, Wet or similar oddities.
We do try to be as helpful as possible and will respond to direct requests through ATC for an inspection.
Any comments from Pilots would be welcome to ensure we get it right as often as possible.

Sir George Cayley
31st Oct 2007, 18:57
In the UK refer to the UK AIP AD section. There-in is defined the runway states and how to promulgate them.

I'm sure ICAO Annex 14 carries similar advice, or if not the Aerodrome Services Manual. It is the aerodrome that declares the runway state.

BUT, BUT in the biggest BUT capital letters imaginable.. It is the aircraft commander's decision whether to take-off or land. Ask the Air Southwest crew that sailed past the end of Midway's runway.:(

ATIS is 3 times an hour updated. RWY inspections are at a minimum daily in some places. If in doubt ask, If still in doubt, go to your alternative. Better to be called cautious than "the deceased":ok:

Oh, and grooves baby. Nothing to do with friction, just water dispersal.

Sir George Cayley

31st Oct 2007, 19:38
As already mentioned, the assessment of runway surface conditions at major UK Airports is normally done by Airfield Operations. If pilot reports or ATC observations indicate that conditions are worse than promulgated, then ATC may transmit an update prefaced "Unofficial Observation ..... ".

Under no circumstances are controllers to pass to pilots information which suggests that conditions are better than the official report.

Tee Emm
2nd Nov 2007, 13:32
I vaguely recall a Boeing publication advice from the Seventies which stated that a runway is wet by defintion if you hold your hand on the runway and your hand comes up wet. That is enough to cause degraded braking efficiency.