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View Full Version : Reverse Thrust on Sanded/Gritted R/W


Whitehorse 1
8th Feb 2010, 13:10
We have started Ops to Airfields and Alternates that Sand/Grit the R/Ws instead of clearing the R/W.( ie- places with temp. well below freezing for lengthy periods and moderates amounts of snow, making snow clearance impractible)

Any thoughts from guys who have experience about the use of idle reverse/ full reverse in these circumstances (B757/B767 size of a/c).

I can see the possibility of "whiteout" but also the possibility of "sandblasting " the airframe.

Many thanks

Whitehorse 1

Tinwacker
8th Feb 2010, 14:13
Welcome to PPRuNe...

I can see the possibility of "whiteout" but also the possibility of "sandblasting " the airframe.

Big problem would be the sandblasting of the engine internals and grit ingestion if the reverser is not cancelled early.

Good experience for this team..

TW

Nightstop
8th Feb 2010, 15:56
I used to operate the 146 into Dagali, Norway in runway conditions such as this. As I'm sure your aware, the 146 isn't equipped with reversers but nevertheless we inhaled, via the aircon system, copiuos amounts of sand during the landing rollout. I suggest you consider the use (or not) of the Packs during landing (subject to manufacturers recommendations of course) :cool:

Whitehorse 1
8th Feb 2010, 17:25
Thanks for the Welcome Tinwacker.

I have infact been here as long as you have. Its just that my previous name, a straight forward "whitehorse" seems to have been "Hijacked".

Back to the topic, I'm hoping some of our Canadian friends here, will have some thoughts.Perhaps they can also comment about packs on or off as indicated by reply number 2.

Checkboard
8th Feb 2010, 17:33
I haven't operated into them, however have been to them on skiing trips and the like. As I understand it, the sand is spread on the snow - which is packed solid, more like solid ice than snow, and the sand is pressed into that surface to provide traction. From the areas I have walked on and examined (hey - I was curious!) I don't think ingestion would be a big issue, unless the sand had just been laid. Following normal procedures of making sure of idle reverse below 60 knots would take care of most of it, I would think. Norwegians I have spoken to say it's not much of an issue - feels more like concrete than snow! I have operated in blowing sand in Australia, and that would probably have been worse for the engines.

clunckdriver
8th Feb 2010, 20:29
Have spent a good portion of my time on such strips, firstly snow if cleared right after its on the ground will give you a dry surface with good friction below about minus ten , the crap about "we cant scrape it at these temps" is just a load of crap, normally used by the airport operator to save money. If you are flying a 727 or anything Russian you can put the reversers in the first class washroom and you will have no problems with injesting sand, if its any of the Air Bus products one needs to be carefull, get the engine anti ice of before touchdown or you will have way too much idle thrust {what a stupid set up this is in our climate} also idle below sixty knots, start the APU before landing so if you do have to shut them down to stop sliding at least one is not left sitting in a dark cold aircraft. We have flown 727/737 / Airbus from sea ice, packed snow and all in between, its no big deal, just get it low and slow over the fence {or snow bank!} no auto land or auto throttle, plonk it on, lots of reverse to kill the top end speed, lots of auto or man brakes , if it cocks of runway heading a bit just let it slide that way, if you kick it straight in a cross wind you may finish of the side, taxi without engine anti ice if able on any Bus product, park it, enjoy the view and the fresh air!

PappyJ
9th Feb 2010, 06:27
Somewhere in the Attic I have some publications for the 767 and 747 regarding this type of operation (Snow, sand, ****). I'll dig around tonight and find them, then post the details. If you're operating a Bus, I can forward a current briefing note regarding the A330 / A320 series.

Whitehorse 1
9th Feb 2010, 09:37
Thanks for the above replies. I'm particularly interested in B767/B757. Hopefully our Tech. Capt. will ask Boeing but please keep the comments coming.
Tahhhh very much