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PompeyPaul
17th Jul 2008, 17:53
This isn't based on anything that happened to me, but just something I was wondering as I cycled to work this morning.

Let's say your flying along, there are cumulus about with heavy showers in them. You are near Gatwick CTR and notice you are within a crescent shape of heavy showers. You can't see through the showers, vis < 1km, ovc above. Only way to avoid going through the heavy rain is to infringe Gatwick CTR.

What would you do ? Fly IMC with non IMC rating through the showers ? Politely ask for special VFR ?

I understand a "superior pilot uses his superior judgement to avoid having to show his superior skill" but just say the above happened what would you ?

foxmoth
17th Jul 2008, 18:07
Speak to LGW, I think you will find them very helpful, they will probably allow you into their airspace if needed and will make sure that as a primary concern you are safe - if possible they will keep you from interfering with normal ops, but I think you will find your safety will have higher priority:ok:

IO540
17th Jul 2008, 19:17
Personally, instrument capable and legal to change flight rules to IFR, I would fly through the rain. It's not a safety hazard. Lightning might be though... and also heavy rain could come out of a CB anyway so you could have a lot of turbulence underneath.

I've never heard of anybody trying this as a reason for a CAS transit. I am pretty sure that quite a few ATC units would give you a short thrift, especially some overseas ones, unless you declared an emergency. And in the situation you describe (trapped) you should do that, fast.

foxmoth
17th Jul 2008, 19:30
instrument capable and legal to change flight rules to IFR, I would fly through the rain

PP did say with non IMC rating so change to IFR not really an option:ugh:

englishal
17th Jul 2008, 19:41
Do whatever it takes. Ask and if nescessary declare a pan and tell them what you are going to do....

Fuji Abound
17th Jul 2008, 20:04
Never even consider becoming IMC without an IMC or IR rating.

If there is no other way tell Gatwick that you need an urgent weather diversion to avoid becoming IMC. There is no need to declare a pan unless they refuse which is very very unlikely. Tell them what you need - request immediate right turn 40 degrees on to heading x and immediate clearance into CAS.

You will get it every time.

Better still before you ever get into that situation go do an IMC rating - even if the clowns do away with it you will be qualified to enter cloud in an emergency even if not legal!

bookworm
18th Jul 2008, 08:37
What does

... a crescent shape of heavy showers ...

mean?

If you go it to the situation, can you not make a 180 and get out of it? Or are you hypothesising that the weather has somehow closed in behind you?

dont overfil
18th Jul 2008, 09:42
Aviate, navigate, communicate, in that order. Do whatever is neccesary to stay VMC.

foxmoth
18th Jul 2008, 10:14
Aviate, navigate, communicate, in that order. Do whatever is neccesary to stay VMC.

But sometimes (and the circumstances quoted seem like one of these occasions), timely communications will help with the Aviating and Navigating:}

StraightLevel
18th Jul 2008, 10:20
Could always do a precautionary landing if there was a suitable field, and wait for the weather to improve.

IO540
18th Jul 2008, 10:56
Could always do a precautionary landing if there was a suitable field, and wait for the weather to improve.

In a helicopter yes, not in a standard club spamcan.

Also, from what I recall, the schools have a rule that the renter is not allowed to fly out of any unprepared field. He has to get one of the instructors to fly it out of there. Sensible really since the field needs to be inspected, measured, etc.

In most cases I've heard of, the plane has to come back out on a trailer with the wings off - costs the owner a few grand. However this is probably because most forced landings are not precautionary landings but engine failure cases.

I don't recall anybody I knew ever doing a genuine precautionary landing due to "impossible" weather - I think that it is a psychologically very difficult thing for the pilot to do.

foxmoth
18th Jul 2008, 11:07
I don't recall anybody I knew ever doing a genuine precautionary landing due to "impossible" weather - I think that it is a psychologically very difficult thing for the pilot to do.

Something I have done, a long time ago, but the right decision at the time with the experience I had then and wx not as forecast, flew it out again when the wx improved - in the circumstances given though I think it would be unnecessary if you spoke to LGW and got their help.

Fuji Abound
18th Jul 2008, 11:50
Bookworm is correct I cant think of any occasions where the weather boxes you in to that extent, unless of course you have pushed on for too long. A 180 almost always does the trick.

I suppose there could be a greater risk of this happening when running through somewhere like Mig Alley where there is only one way in and one way out in terms of CAS.

I can think of more than a few occasions on the other hand when IFR a turn for weather avoidance seems sensible.

I recall recently dodging the CBs around Southampton and some particularly heavy downpours when the controller seemed intent on vectoring me through the worst of it.

Interesting when a CAT at the same time wanted to be vectored so far to the west he had to be warned that he was about to leave CAS.

LowNSlow
19th Jul 2008, 05:16
If you are boxed in by clouds and CAS, get onto the people controlling the CAS, you can't talk to clouds!

While rain isn't in itself dangerous it can play merry Hell with the paint finish of your prop. The one time I flew my Cub, with it's lovingly varnished and balanced wooden Evra prop, into a rain shower it stripped the varnish off despite me using reduced revs when I entered the shower. Same thing happened with the steel Fairey-Reed prop on my Auster. Now I stay out of the rain if I possibly can! An added bonus of flying in rain is that you get to find out where your aeroplane leaks. :eek:

rjay259
19th Jul 2008, 21:49
I think I would speak with gatwick director they are there to provide a service to everyone commercial and GA alike.
If the viz just happened to be 'that bad' I wouldnt bother going through the rain as there could be severe down drafts or what ever, not what a light a/c would like.

I do find it amazing that people do not like speaking with or will avoid speaking with controllers like gatwick or solent. They are just people with a job to do and their main priority is the SAFE transit of all a/c.

So I wouldnt fly through the rain a 180 and speak with gatwick to get assistance.

259.

IO540
19th Jul 2008, 21:59
Same thing happened with the steel Fairey-Reed prop on my Auster.

That's weird - I have flown through the heaviest rain many times and never got any problems with the prop. I have an aluminium 3-blade Hartzell one. The paint was completely unaffected.

LowNSlow
20th Jul 2008, 11:30
IO540 is your prop finished in two-pack or something equally durable? Mine is simply finished with conventional gloss paint which I assume is cellulose. I'll get around to stripping and repainting it one day. I've seen leading edge protection tape for props, does this have any noticeable effect on the performance?

Cusco
20th Jul 2008, 14:15
I've never heard of anybody trying this as a reason for a CAS transit. I am pretty sure that quite a few ATC units would give you a short thrift, especially some overseas ones, unless you declared an emergency

My logbook tells me that on 8.1.2000, while ferrying my a/c back from its 50 hr from N Weald to the strip near Honington, I asked Stansted for a zone transit (to avoid going round 3 sides of a square).

It was of course refused.

Five minutes later, travelling to the east towards Chelmsford it was plain to me that my path was completely blocked by a mass of CBs and rain.

I put this to Essex Radar who immediately cleared me through Stansted zone and along the line of the runway, not across it.

Never been granted a transit since, to the extent I've given up asking.

But it can be done for Wx.

Cusco;)

IO540
20th Jul 2008, 14:17
I don't know what Hartzell use in the factory but whatever that was, 99% was still there after 6 years. At the overhaul it was just an aerosol can job (with primer first) but that is holding fine.

2-pack paints should be excellent. One can get 2-pack clear paint too.

I'd ask metal prop overhaulers what they use, because they cannot have it all coming off in rain, otherwise people would moan.

Paints are bit of a problem because e.g. the Lycoming grey would come right off within 6 months, and that was on the engine! Lycoming blamed it on a bad batch of paint...

omcaree
20th Jul 2008, 14:33
I have been in a situation similar to this. Boxed in by Heathrow, Luton and rain (not impossible to fly through, but undesirable with nervous passengers). A 180 was an option, but before resorting to that (and 3nm or so before hitting the rain) I gave Luton a call and they were happy to help. They advised me of a heading to their overhead, without me even asking, which more or less coincided with the VFR lane, so maybe I was luck in that respect. From there I got my self around the rain with no difficulties.

I did give the controller a scare as there was something wrong with my mode C meaning I was indicating an altitude ten times higher than I was flying. Needless to say I was promptly asked to switch that off!

If you are boxed in by clouds and CAS, get onto the people controlling the CAS, you can't talk to clouds!

This didn't seem to stop my pax screaming at them! :}

Keef
20th Jul 2008, 14:51
If you don't like the weather ahead, a 180 is always a good option.

I've never yet been refused a transit of CAS when weather was a problem.

I've also not been refused a transit of Stansted in something close to ten years. They used to refuse, but I don't think they do so now unless traffic is very heavy. If I can't get a call in on Essex Radar within a couple of minutes, I know to route around.