A nagging question before my GST...
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A nagging question before my GST...
I had my first attempt at the GST dashed last week by terrible visibility for my navigation. In the route given to me however, there was one section which seemed a tad nasty. I have my test tomorrow but want to clear my head of this nagging question.
My first leg was from Clacton to Sevenoaks, over Sevenoaks my MSA was 2400ft due to a particularly large obstruction on top of a particularly large hill. According to my chart I'm in class A from 2500' in this area. Am I right in believing that I only had a 100ft corridor between my MSA and busting controlled airspace? My examiner told me I wasn't allowed below my MSA even though legally I was allowed to. My intended height was 2450ft amsl but I was very reluctant about having to do so. Was this just a route to seriously test my ability or am I missing something here? I haven't had the opportunity to talk to my instructor about it but I feel like I'm missing something. Thanks
My first leg was from Clacton to Sevenoaks, over Sevenoaks my MSA was 2400ft due to a particularly large obstruction on top of a particularly large hill. According to my chart I'm in class A from 2500' in this area. Am I right in believing that I only had a 100ft corridor between my MSA and busting controlled airspace? My examiner told me I wasn't allowed below my MSA even though legally I was allowed to. My intended height was 2450ft amsl but I was very reluctant about having to do so. Was this just a route to seriously test my ability or am I missing something here? I haven't had the opportunity to talk to my instructor about it but I feel like I'm missing something. Thanks
Why do it if it's not fun?
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My examiner told me I wasn't allowed below my MSA even though legally I was allowed to
As a CPL instructor, I find a fair proportion of my students don't understand MSAs as they relate to VFR flight. For your examiner to be doing anything other than encouraging you to know the rules and exploit them to your benefit seems a bit strange to me, but might help explain why so many of my students believe, incorrectly, that they can't fly below MSA!
However, if that's what he asked you to do, then you either have to fly at 2400' (which is very common under the TMA, even without MSA issues, so keep a very good lookout), or route around the obstacle. I would not recommend flying at 2450' - it is generally accepted that you need to be 100' below airspace, although I don't believe that's written down anywhere. But there is nothing wrong with flying at your MSA.
Good luck!
FFF
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eh?
I was taught when VFR the MSA was calculated for the scenario where one inadvertently flew into cloud.
I certainly was never told I 'had' to fly it as a minimum whilst still VFR and didn't during my PPL GST.
If you are VFR and there is a hill with an obstruction, you are not about to fly into it are you?
Practically every VFR flight I do requires flight under airspace where flight above/at MSA wouldn't be legal (by my calculation method). I can't see you can be held to it in the test.
If I'm totally wrong I'm more than happy to be corrected by an FI, CFI or Examiner.
I certainly was never told I 'had' to fly it as a minimum whilst still VFR and didn't during my PPL GST.
If you are VFR and there is a hill with an obstruction, you are not about to fly into it are you?
Practically every VFR flight I do requires flight under airspace where flight above/at MSA wouldn't be legal (by my calculation method). I can't see you can be held to it in the test.
If I'm totally wrong I'm more than happy to be corrected by an FI, CFI or Examiner.
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Just answering quickly, as your GST is tomorrow.
That MSA requirement sounds odd. MSA is important if you are flying IMC, and can't see things till you hit them, but a skills test is in VMC, so you can see and avoid.
I seem to recall a mast between Sevenoaks and Brands Hatch, is this what you mean? It is easy enough to see and avoid. I passed near there at around 2200 ft recently without feeling in any danger of hitting the mast. I did pay attention to the Biggin ATZ, the Gatwick CTA and the LTMA 2500 though.
One more tip: if there is a North or South wind over the hills watch your height very carefully.
That MSA requirement sounds odd. MSA is important if you are flying IMC, and can't see things till you hit them, but a skills test is in VMC, so you can see and avoid.
I seem to recall a mast between Sevenoaks and Brands Hatch, is this what you mean? It is easy enough to see and avoid. I passed near there at around 2200 ft recently without feeling in any danger of hitting the mast. I did pay attention to the Biggin ATZ, the Gatwick CTA and the LTMA 2500 though.
One more tip: if there is a North or South wind over the hills watch your height very carefully.
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This is what really frustrated me at the time. I knew I could legally make my life a hundred times easier by giving myself a couple of 100' margin but the examiner had explicitly told me I wasn't allowed below my MSA. I would have been happy to fly my MSA if nothing had been said but was worried if one momentary blip took me below it. At least I can't be given the same route tomorrow so it could be worse I guess. Lucky i couldn't go ahead with it looking back. Blessing in disguise and all that.
Surely instructors, and examiners, should encourage students to think for themselves?
Mind you, I've also flown with my share of such who didn't either, and far too many who think that applying substantial extra safety factors beyond regulations is essential and will try to fail you if you don't.
VFR, 500ft rule applies - MSA is an IFR concept - albeit a useful one to simplify flight planning VFR.
My opinion? Make sure you can see it, stay at-least a mile away from the obstacle, and allow yourself a few hundred feet below the airspace. If the examiner has a problem with that, ask him to show you the rule which prohibits flying like that, and if he still fails you, report him to the CAA. Which won't happen - pretty much anybody will see sense if presented with the regulations.
G
Mind you, I've also flown with my share of such who didn't either, and far too many who think that applying substantial extra safety factors beyond regulations is essential and will try to fail you if you don't.
VFR, 500ft rule applies - MSA is an IFR concept - albeit a useful one to simplify flight planning VFR.
My opinion? Make sure you can see it, stay at-least a mile away from the obstacle, and allow yourself a few hundred feet below the airspace. If the examiner has a problem with that, ask him to show you the rule which prohibits flying like that, and if he still fails you, report him to the CAA. Which won't happen - pretty much anybody will see sense if presented with the regulations.
G
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Seeing as I have the same examiner tomorrow, should I make a point of bringing this up with my instructor before I take the test? Rubbing up my examiner the wrong way isn't what I really intended on doing but I'm in the right here. I don't want to make my life harder than it already is when I don't need to.
That's the one - it would have made a very handy visual reference if nothing else 
I seem to recall a mast between Sevenoaks and Brands Hatch, is this what you mean?
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If you're still reading this on the 7th, why aren't you in bed yet!?
Seriously though, just talk it through with your instructor. Routing around (I would go for several miles clearance in oder to mitigate navigation errors) and seeing and avoiding is the way any sensible pilot would do it in real life.
Giving yourself 50' below controlled airspace is a recipe for cock up.
Your instructor should be open to reasoned debate on this so if he instists on you flying the same way then at least you'll know why. With respect, it does seem likely that you may be misinterpreting what he is driving at with his MSA.
Edit: Thinking about it, he is probably not asking you to fly between MSA and controlled airspace, simply to be aware of what the MSA and local class D is so that should you find yourself in IMC, you can remain clear of obstacles and infringements.
Best of luck,
FF
Seriously though, just talk it through with your instructor. Routing around (I would go for several miles clearance in oder to mitigate navigation errors) and seeing and avoiding is the way any sensible pilot would do it in real life.
Giving yourself 50' below controlled airspace is a recipe for cock up.
Your instructor should be open to reasoned debate on this so if he instists on you flying the same way then at least you'll know why. With respect, it does seem likely that you may be misinterpreting what he is driving at with his MSA.
Edit: Thinking about it, he is probably not asking you to fly between MSA and controlled airspace, simply to be aware of what the MSA and local class D is so that should you find yourself in IMC, you can remain clear of obstacles and infringements.
Best of luck,
FF
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VFR flight would not be possible in a lot of places if there was a rule that requires you to stay above the MSA. About a third of the Netherlands lies underneath the Schiphol TMA which is class A from 1500' upwards. The MSA is between 1800' and 2300', depending on the exact location due to a few well known tall masts but apart from those masts there's nothing to bump into at 1000'. So we all fly at roughy that altitude with no problem whatsoever.
What you should NOT do is take the grid MSA (the number that's printed on your chart every 1/2 degree of lat/long) as your flight MSA because that's going to restrict you severely. Instead draw your route, take a reasonable lateral safety margin (5 miles or so, depending on your expected navigational performance) and calculate your MSA based on the large objects or high ground you find within that safety margin.
That usually solves any routing/MSA problem you have. And if there is indeed a large obstacle in your way, you now know it's there and can re-plan accordingly. Or use it as a waypoint: If I know I'm going to encounter a tall mast or something during my flight which is a serious safety hazard which cannot be avoided, I want that to be in my plog so that I'm looking out for it.
(I often use the Hilversum TV tower as a waypoint. It's a very conspicous landmark even in low visibility. It's also 673' tall in an area where my planned altitude is normally 1000' or so.)
What you should NOT do is take the grid MSA (the number that's printed on your chart every 1/2 degree of lat/long) as your flight MSA because that's going to restrict you severely. Instead draw your route, take a reasonable lateral safety margin (5 miles or so, depending on your expected navigational performance) and calculate your MSA based on the large objects or high ground you find within that safety margin.
That usually solves any routing/MSA problem you have. And if there is indeed a large obstacle in your way, you now know it's there and can re-plan accordingly. Or use it as a waypoint: If I know I'm going to encounter a tall mast or something during my flight which is a serious safety hazard which cannot be avoided, I want that to be in my plog so that I'm looking out for it.
(I often use the Hilversum TV tower as a waypoint. It's a very conspicous landmark even in low visibility. It's also 673' tall in an area where my planned altitude is normally 1000' or so.)
Last edited by BackPacker; 7th Jun 2011 at 21:53.
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I would just chill a bit before your test and do your best to fly it like any other flight.
I can't really figure it other than it might have been a hint that the planning was flawed or not to the examiner's liking.
I did once have an instructor who questioned why I had calculated MSA and wasn't flying it. I didn't bother to explain and chose never to fly with him again.
However you look at it, there is no legal requirement to fly at or above a calculated MSA during a VFR flight in the UK. Take one look at the Eastern Stansted transponder mandatory zone, then figure how far below MSA (by any of the popular calculation methods) you would have to be to fly in it.
It was made more than clear to me that the reason to calculate MSA for VFR flights was insurance against being stuck in cloud. If the 180 degree turn didn't work, climb to MSA whilst talking to whoever controls the airspace you just busted and live to tell the tale. OK more seriously one would look for routes where it wouldn't be an issue and be very aware of where it might be, but you get the concept.
I can't really figure it other than it might have been a hint that the planning was flawed or not to the examiner's liking.
I did once have an instructor who questioned why I had calculated MSA and wasn't flying it. I didn't bother to explain and chose never to fly with him again.
However you look at it, there is no legal requirement to fly at or above a calculated MSA during a VFR flight in the UK. Take one look at the Eastern Stansted transponder mandatory zone, then figure how far below MSA (by any of the popular calculation methods) you would have to be to fly in it.
It was made more than clear to me that the reason to calculate MSA for VFR flights was insurance against being stuck in cloud. If the 180 degree turn didn't work, climb to MSA whilst talking to whoever controls the airspace you just busted and live to tell the tale. OK more seriously one would look for routes where it wouldn't be an issue and be very aware of where it might be, but you get the concept.
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Oh, to add (can't edit my post now for technical reasons): The Jeppesen VFR charts print the grid MSA directly on the chart for each 1/2 degree lat/long, while the UK CAA charts print the highest known elevation. To which you need to add 1000' to get the MSA.
G
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It was made more than clear to me that the reason to calculate MSA for VFR flights was insurance against being stuck in cloud. If the 180 degree turn didn't work, climb to MSA whilst talking to whoever controls the airspace you just busted and live to tell the tale.
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I think the CAA charts publish the highest known elevation or obstruction. Since obstructions below 300 feet agl are not necessarily known to the CAA, because they are not required to be lit, one should also take that additional 300 feet into account in one's calculations.
flybymike, that old chestnut is incorrect. As stated in the 'Reference to Air Information' printed on the chart, CAA MEFs are 'based on information available concerning the highest known feature in each quadrangle, including terrain and obstacles and allowing for unknown features'.
For example, on the old Edition 33 (yes, I know it's out of date!), if you look at the MEF for the quadrangle which includes Chivenor, the highest elevation is 883 ft. Yet the MEF is '1.2', i.e. 1200 ft. But because someone might have sneakily put up a 299.99 ft obstacle on top of the 883 ft hill, the MEF is 883+300 = 1183, rounded up to 1200 ft.
There is no need for the'additional 300 ft' to be added to the MEF.
For example, on the old Edition 33 (yes, I know it's out of date!), if you look at the MEF for the quadrangle which includes Chivenor, the highest elevation is 883 ft. Yet the MEF is '1.2', i.e. 1200 ft. But because someone might have sneakily put up a 299.99 ft obstacle on top of the 883 ft hill, the MEF is 883+300 = 1183, rounded up to 1200 ft.
There is no need for the'additional 300 ft' to be added to the MEF.
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A bit late now, I know, but might the intention of this be for you to adjust your route to avoid the pinch? The route given to me for my test, if drawn direct, took me directly over a glider site. Part of the test was for me to notice this and adjust my route to make room around it. Could it be that your examiner is being heavy about the MSA to encourage you to plan your route so that you have more headroom?
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Quote:
I can't help feeling that flying into a cloud whilst on a test might just be a fail.
I can't help feeling that flying into a cloud whilst on a test might just be a fail.
MSA - safety altitude to climb to if one inadvertently flew into IMC
One would rather hope that during a test a candidate would have more sense than risk flying at VFR minima and the possibility of inadvertently flying into cloud.
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Why are we talking about the MEF figures printed on a chart?
The safety altitude is 5nm either side of the planned track, which might give this student a lot more room to meet his examiners request than the MEF figure on the chart.
It's probably too late now, but if it was me I'd discuss the examiners requirement with them, explaining that I recognised that his request left a very small window, and increased the potential for an airspace bust. I'd ask if he could allow me to fly below MSA on this leg, bearing in mind where the obstacles are that are causing this high safety altitude, and explain that if that isn't acceptable, then I'm using my judgement to reduce that risk by planning a longer route which had a lower safety altitude.
I can't see how the examiner could be anything but impressed that you had thought about the issue, and recognised the risk, and come up with a plan to mitigate the risk.
dp
The safety altitude is 5nm either side of the planned track, which might give this student a lot more room to meet his examiners request than the MEF figure on the chart.
It's probably too late now, but if it was me I'd discuss the examiners requirement with them, explaining that I recognised that his request left a very small window, and increased the potential for an airspace bust. I'd ask if he could allow me to fly below MSA on this leg, bearing in mind where the obstacles are that are causing this high safety altitude, and explain that if that isn't acceptable, then I'm using my judgement to reduce that risk by planning a longer route which had a lower safety altitude.
I can't see how the examiner could be anything but impressed that you had thought about the issue, and recognised the risk, and come up with a plan to mitigate the risk.
dp
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It's probably too late now, but if it was me I'd discuss the examiners requirement with them, explaining that I recognised that his request left a very small window, and increased the potential for an airspace bust.
in my head I just had to accept it and move on.Test was cancelled today anyhow
. With gusts up to 27 knots I couldn't really pursade myself to go up as much as I wanted to get this bloody thing done. Maybe next time...