Unique From Switzerland, joined Mar 2003, 1703 posts, RR: 38 Posted (10 years 8 months 2 weeks 1 day 22 hours ago) and read 3176 times:
I'd like to know the procedures on other airports regarding the deicing procedure for propeller driven aircraft.
At ZRH, remote deicing is done with running engines. Spinning propellers, however, are not allowed as it is too dangerous for the deicing truck driver in case of hitting the propeller as well as deicing fluid is sprayed into the propeller by error, causing damage to the aircraft.
I've heard of MUC and CPH doing remote deicing ONLY irrespective of aircraft tpye.
Can anyone please share the deicing habits on other airports?
PSU.DTW.SCE From United States of America, joined Jan 2002, 7193 posts, RR: 29 Reply 1, posted (10 years 8 months 2 weeks 4 hours ago) and read 3070 times:
Remote versus gate deicing is a decision that is made by the individual airlines or airports. It has nothing to do with aircraft type. Instead it has to do with the collection of the glycol in the deicing fluid. Deicing fluid is a polluntant, therefore there are strict regulations for its collection to prevent it from getting into the ground water. Airports usually have special deicing pads where they can collect the glycol and recycle it. Sometimes this can be done at the gate but it is generally more difficult to collect and can cause a mess with other ramp operations such as servicing the aircraft and baggage handling. All the deicing fluid would get tracked around the airport and airplanes making a mess.
I have never heard of a deicing being done with engines running. In all cases in the United States, engines are to be shut down to perform deicing procedures. This is done to prevent the fluid from being ingested into the engine, to prevent fumes from entering the cabin air supply, and to prevent the dangers of jet blast, and yes for the obvious reasons of a spinning propellor too.
At DTW, most deicing by Northwest is done remote. Other airlines usually perform gate deicing. Oftern if there is a need to de-ice and there is time to perform deicing on RON aircraft before departure, this will be done at the gate in order to reduce the likelyhood of delays. Otherwise deicing is done at remote pads on the airfield.
Unique From Switzerland, joined Mar 2003, 1703 posts, RR: 38 Reply 2, posted (10 years 8 months 2 weeks ago) and read 3056 times:
Thanks PSU.DTW.SCE! At ZRH, remote deicing is done with engines running hence the time spent in the pad can be as little as two minutes.
Your point about deicing fluid being ingested by the jet engine is a very valid one. Apparently, it's not a problem here at ZRH!
I'll try to convince the deicers to also treat prop driven aircraft on the remote pad with running engines. Since they have to be careful with jet engines, they can also be careful with spinning propellers.
Since the engines are shut down for deicing in the U.S., do you then have GPU's availabe at the remote deicing pads? APU's not always work...
PSU.DTW.SCE From United States of America, joined Jan 2002, 7193 posts, RR: 29 Reply 3, posted (10 years 8 months 1 week 6 days 9 hours ago) and read 3034 times:
I don't work at DTW, I work at a smaller spoke city in State College, PA. We only get prop aircraft like Saab 340's, Dash-8's, and Jetstream-41's.
Our de-icing procedures are as follows.
1) Load the aircraft (passengers & baggage). We do not have jetways, which is one of the reasons we do not de-ice on the ramp as passengers would have to walk through the mess.
2) Engines are started, with the aide of a GPU. The aircraft taxis away from the terminal to the de-icing pad which is about 100 yards away. Engines are then shut-down.
3) The aircraft is de-iced on the pad.
4) After de-icing is complete, the GPU, which was towed over by a tug, is reconnected to the aircraft.
4) Engines are restarted and and the aircraft is now set to depart.
The deicing pad has a special drainage system that collects the deicing fluid. The glycol is then removed and recycled. This prevents it from running off into local streams. The Dept. of Environmental Protection has been on the airport's case a few times because they found traces of deicing fluid in local streams. We have unique geology in the area and sinkholes on the airport property. The problem was that runoff that contained some deicing fluid had gotten into the sinkholes which go directly into the groundwater and streams. The sinkholes have been filled with concrete to prevent pollution from the airport getting into them.
Part of the reason that propellor aircraft are deiced with the engines shut down it to deice the prop and to be able to get all the wing surfaces. A spinning propellor would make it more difficult to hit the leading edges and would also deflect a spray fluid all over the place. It just sounds like too risky a procedure. I'm never a big fan of being anywhere close to a spinning propellor. Disconnecting the GPU after engine-start is enough for me.
Unique From Switzerland, joined Mar 2003, 1703 posts, RR: 38 Reply 4, posted (10 years 8 months 1 week 6 days ago) and read 3031 times:
Thanks a lot! This basically matches our procedures except that ZRH / LSZH), Switzerland">ZRH is much bigger than your airport and the deicing pads are further away (sometimes across a runway).
I'm just trying to set up a procedure to prevent on-stand deicing. The mess left behind is a real pain and needs to be cleaned every time by a jetbroom truck (like a giant vacuum cleaner).
It also seems that aircraft operators are not willing to expose their prop aircraft to eventual damage to the propellers due to accidential spray of fluid into the spinning props. To get to the leading edges is another valid point, many thanks!
Over here, winter is as good as over, so it leaves me some time to work out revised procedures till the deicing season starts again in October.
Many thanks indeed for all contributions to this topic! Cheers