De-icing gear Hobart

[ajw373]

Warm fuel.

It is obviously a way that it can be done and it must be safe otherwise they wouldn't be allowed to do it. So what's the issue?

 

[RooFlyer]

It is obviously a way that it can be done and it must be safe otherwise they wouldn't be allowed to do it. So what's the issue?

No, no issue at all. You may have noticed up the thread that I said the particular HBA incident was "pretty inconsequential". I'm just having fun here.

I wonder what 'warm fuel' means? I'm guessing they just left the wings to thaw out. If it works for the prevailing conditions - sure, why not? But I'm not sure what preventative measures they took to stop the ice re-forming (probably judged not to be a risk in this case). 'De-icing' - such as performed on nearly all the planes I fly on in Canada and northern USA in their winter - uses stuff like ethylene glycol sprayed over selected or all surfaces on the plane. In a heated, thin state it just helps removed of existing ice. But in a thickened, cold state, it helps prevent ice re-forming by clinging to the surface until the plane's take-off speed causes it to thin and stream over the surfaces.

Now in conditions of, say, freezing rain at HBA, I wonder what method they would choose? If its working.

Although I'm an HBA resident, I've never seen the gear that's there. I might try to find out.

 

[BD1959]

It is obviously a way that it can be done and it must be safe otherwise they wouldn't be allowed to do it. So what's the issue?

The issue is: if there's a further delay allowing the fuel to cool and ice to reform ... how do you then get rid of it?

(I'll fetch the popcorn!!)

Regards,

BD

 

[markis10]

International or not - gear should be available.

I wonder how they warm the fuel? Put a little burner under the fuel truck?

They dont warm the fuel, its warmer than the aircraft because its been underground where temperatures are higher than on the apron. On the plane fuel is warmed via return flow from the engine, see this http://www.google.com.au/url?sa=t&r...jr6j3Y36R-N034A&bvm=bv.48572450,d.aGc&cad=rja

 

[Austman]

The issue is: if there's a further delay allowing the fuel to cool and ice to reform ... how do you then get rid of it?

(I'll fetch the popcorn!!)

Regards,

BD

I believe that's why it's left to last? Everything else is ready, then they load the warm fuel as a final measure, just minutes before take-off. That's what seemed to happen on my flight anyway.

 

[BD1959]

I believe that's why it's left to last? Everything else is ready, then they load the warm fuel as a final measure, just minutes before take-off. That's what seemed to happen on my flight anyway.

And then a passenger falls ill .....


(munch, munch)


Regads,

BD

 

[Austman]

And then a passenger falls ill .....


(munch, munch)


Regads,

BD

Probably would not matter? On recollection I think the pilot said it was cold fuel (from the earlier flight) that was the actual cause of the wing ice. Replacing that fuel probably eliminated both the ice and the cause of it.

 

[BD1959]

Probably would not matter? On recollection I think the pilot said it was cold fuel (from the earlier flight) that was the actual cause of the wing ice. Replacing that fuel probably eliminated both the ice and the cause of it.

Cold fuel in the tanks (especially overnight) will accelerate the icing process on the wings. Obviously, adding a a warmer fuel will increase the overall tank temperature and *may* lead to deicing, but allow the melted ice to still sit on the top of the wing. If the ambient temperature is cold enough and if a delay is long enough, the tank temperature will reduce again and icing can recur.

(chompy, chompy)

Regards (and regads!)

BD

 

[Austman]

Cold fuel in the tanks (especially overnight) will accelerate the icing process on the wings. Obviously, adding a a warmer fuel will increase the overall tank temperature and *may* lead to deicing, but allow the melted ice to still sit on the top of the wing. If the ambient temperature is cold enough and if a delay is long enough, the tank temperature will reduce again and icing can recur.

(chompy, chompy)

Regards (and regads!)

BD

Not much of what you say seems applicable for my flight. It wasn't parked overnight and the ground air temperature was around +10 degrees. It seems that "fuel frost" is a problem more due to ground humidity than ground temperature and can happen even in quite warm climates.

I can't see how with a +10 degrees air temperature, the fuel temperature (of the new warmed fuel) is going to drop to below freezing again.

I'd imagine an overnight park would have enough time to bring any wing fuel to ambient air temperatures. And then the aircraft is refuelled before the flight. The air temperature at HBA has not dropped below zero this June.

Having de-icing equipment is probably pretty important at HBA, but alternatives seem to be working, at least for now.

 

[BD1959]

Not much of what you say seems applicable for my flight. It wasn't parked overnight and the ground air temperature was around +10 degrees. It seems that "fuel frost" is a problem more due to ground humidity than ground temperature and can happen even in quite warm climates.

I can't see how with a +10 degrees air temperature, the fuel temperature (of the new warmed fuel) is going to drop to below freezing again.

I'd imagine an overnight park would have enough time to bring any wing fuel to ambient air temperatures. And then the aircraft is refuelled before the flight. The air temperature at HBA has not dropped below zero this June.

Having de-icing equipment is probably pretty important at HBA, but alternatives seem to be working, at least for now.

Hi Austman,

I'm sure that a full risk analysis has been performed with respect to the alternatives and the potential of not having de-ice at HBA. After all, we wouldn't want the holes in that cheese to align.

Regards,

BD

 

[ajw373]

What is also important is the type of ice we are talking about in places like Hobart (and Canberra) etc is frost. This is a bit different to the full on ice they have in much colder climates.

Now I know that none of as experts in this field, but simple fact is airlines in this country do not fly if it is dangerous to do so. So I trust that what ever procedure they are using is safe and effective in the given situation.

 

[jb747]

What is also important is the type of ice we are talking about in places like Hobart (and Canberra) etc is frost. This is a bit different to the full on ice they have in much colder climates.

Now I know that none of as experts in this field, but simple fact is airlines in this country do not fly if it is dangerous to do so. So I trust that what ever procedure they are using is safe and effective in the given situation.

As far as I know there is very little de-icing equipment in Australia. Certainly nothing that a European or Canadian would recognise anyway. Sort of fits in with the lack of decent nav aids....