PPL Diversions
All good advice on how to pass the flight test. Once you have passed the ride come back to the boards and we can talk about how to navigate in the real world. ( hint most of what you have to learn to pass the flight test will be irrelevant )
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Once again, Foxmoth, TOO MUCH HEAD DOWN TIME! Good grief, how hard is it to do a 180 if you have the vaguest idea of the compass heading you had been following? Certainly a maneuver that can be done without compromising the lookout. Step two once you have turned around, ask for help on the radio! If there is another reasonable being in the aircraft, capable of looking out and holding it right side up, you might have time for drawings and calculations.
Of course, there is always the big red handle! How many of you Pprunes read about the fancy Cirrus with all the bells, whistles, navaids, gadgets, buttons etc which running into a few clouds not far from Shenington Gliding Club last year, spent a few minutes programming into his computer a 180 turn to go back to Turweston....when he looked up again, the canopy view was entirely GREEN....as the Cirrus was seeking the quickest way to return to earth. He panicked and pulled the jolly red handle, which deployed the Cirrus parachute and the whole chuting match landed in a tree near Horton, near Wroxham, near Banbury. Walked away, but how many times will the insurance companies wear it, I wonder?
Of course, there is always the big red handle! How many of you Pprunes read about the fancy Cirrus with all the bells, whistles, navaids, gadgets, buttons etc which running into a few clouds not far from Shenington Gliding Club last year, spent a few minutes programming into his computer a 180 turn to go back to Turweston....when he looked up again, the canopy view was entirely GREEN....as the Cirrus was seeking the quickest way to return to earth. He panicked and pulled the jolly red handle, which deployed the Cirrus parachute and the whole chuting match landed in a tree near Horton, near Wroxham, near Banbury. Walked away, but how many times will the insurance companies wear it, I wonder?
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I would heartily recommend foxmoth's "bottom of the DI" trick, I learned it through experience.
The first time I blundered into cloud, I wasted stupid amounts of time deciding whether to turn left or right because of nearby airspace, then having started to turn, struggled to add 180 to the previous heading I sort of remembered while terminating a weather-related conversation with Farnborough Radar. Fortunately, sanity prevailed and I decided to head South-West regardless, because it was roughly the right direction.
Equally fortunately, this must have happened rather faster than it felt at the time, because I only had 45 degrees of bank on when I next checked the AI.
I learned something from this. When the unexpected happens, my IQ gets closer to single digits than three, so it really helps to do the thinking on the ground beforehand, so that in the air I can just choose which plan to follow. I also decided to go for an IMC or IR.
Also, KISS!
KISS principle - Wikipedia, the free encyclopedia
Lookout was not an issue, as it had gone all white outside...
The first time I blundered into cloud, I wasted stupid amounts of time deciding whether to turn left or right because of nearby airspace, then having started to turn, struggled to add 180 to the previous heading I sort of remembered while terminating a weather-related conversation with Farnborough Radar. Fortunately, sanity prevailed and I decided to head South-West regardless, because it was roughly the right direction.
Equally fortunately, this must have happened rather faster than it felt at the time, because I only had 45 degrees of bank on when I next checked the AI.
I learned something from this. When the unexpected happens, my IQ gets closer to single digits than three, so it really helps to do the thinking on the ground beforehand, so that in the air I can just choose which plan to follow. I also decided to go for an IMC or IR.
Also, KISS!
KISS principle - Wikipedia, the free encyclopedia
Lookout was not an issue, as it had gone all white outside...
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Once again, Foxmoth, TOO MUCH HEAD DOWN TIME
How much head up time do you need? If it takes more than a fraction of a second to do ANY of the elements I have used then you have a problem - glance down at the bottom of the DI , turn 180, glance at your pre planned drift for last leg - eyes outside, glance at chart to check wind and then eyes outside while your brain thinks about how to apply it then adjust heading, probably 2 seconds total head down time in 60! If you are in the poo it is surprising how hard brain failure can make even simple tasks like turning 180. Radio is great, but sometimes I am non radio - surprising I know, but some of us do occasionally fly aircraft without that sort of advanced equipment!
Drawing the line works the same, should only be done once out of trouble and, if you add in putting some time markers on you line (using your thumb) you might just extend time taken to 3 seconds in 60 for that job!
The time you will end up with a lot of head down time is as soon as you start using any sort of hand held mechanism, and even reprogramming a GPS will probably have more head inside time than this method.
I have used and taught this for many years now with no problem of students keeping their head inside.
Last edited by foxmoth; 20th Feb 2012 at 08:38.
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Of course, there is always the big red handle! How many of you Pprunes read about the fancy Cirrus with all the bells, whistles, navaids, gadgets, buttons etc which running into a few clouds not far from Shenington Gliding Club last year, spent a few minutes programming into his computer a 180 turn to go back to Turweston....when he looked up again, the canopy view was entirely GREEN....as the Cirrus was seeking the quickest way to return to earth. He panicked and pulled the jolly red handle, which deployed the Cirrus parachute and the whole chuting match landed in a tree near Horton, near Wroxham, near Banbury. Walked away, but how many times will the insurance companies wear it, I wonder?
(I am not normally one to stick up for some of the mugs who have pulled the chutes)
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In view of some of the comments re lookout the following link might be interesting...
http://www.msf-usa.org/motion.html
http://www.msf-usa.org/motion.html
Wind angle <15 deg off track, no drift & full wind speed effect on GS
Wind angle <30 deg off track, half max. drift & half wind speed
Wind angle <45 deg off track, 3/4 max. drift & 1/4 wind speed
Wind angle 60-90 deg off track, max. drift & no wind speed effect on G/S
Wind angle <30 deg off track, half max. drift & half wind speed
Wind angle <45 deg off track, 3/4 max. drift & 1/4 wind speed
Wind angle 60-90 deg off track, max. drift & no wind speed effect on G/S
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For wind 60 degrees off track, I would correct for groundspeed by 1/2 of max drift.
applying clock method correctly you use angle off direct for drift/xwind, and 90 - angle off for head/tailwind component.
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In the context of looking out, looking in, looking out..., I wonder how "Change Blindness" affects lookout. Quite badly, I suspect.
Here are some examples:
J. Kevin O'Regan
(Scroll down to Change Blindness Demonstrations).
The Royal Institution Christmas Lectures had an example too.
Here are some examples:
J. Kevin O'Regan
(Scroll down to Change Blindness Demonstrations).
The Royal Institution Christmas Lectures had an example too.
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Peterh337, I have dredged up the original thread....for your delectation. I think it truly makes the point that until you can pilot the simple aeroplane safely, don't put your trust in gadgets!
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Tried to fly to Kemble from Goodwood,Wx not quite as forecast, cloud got lower and lower, got Brize weather and terrible so decided to 180, ideal would have been follow the M4, then down A34 but cloud was too low along M4 so needed a proper 180 - this also showed up another problem with your
when you are in this situation you may be low down and below radar - neither Brize or Farnborough could see us, so, yes I could talk to them, but they were not a lot of help! This was a LAA type with minimal instruments so alternatives such as climbing (not a good option of course if you are not trained and current in IF) were not available.
With many hours flying behind me and the right techniques it was not a problem, without the hours at least having the right technique would make it less of a drama.
Step two once you have turned around, ask for help on the radio!
With many hours flying behind me and the right techniques it was not a problem, without the hours at least having the right technique would make it less of a drama.
Last edited by foxmoth; 21st Feb 2012 at 08:26.
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The only "180" I can recall was in 2002, shortly before I got the IMCR. I was flying back to the coast with a GF... the cloudbase was gradually dropping 2000 1900 1800 and by the time I turned the autopilot down to about 1000 and was just below it I decided this is getting a bit close (given the south downs ahead) so I landed at Blackbushe. Flew out the following morning. Back then I was a fresh PPL and did not even know what an MSLP chart was
I have done plenty of other diversions but they were more "orderly" and usually due to some place being below approach minima.
I have done plenty of other diversions but they were more "orderly" and usually due to some place being below approach minima.
Best advice I got from an experienced pilot when I was a low houred PPL was to follow ground features (road, rivers, railway tracks, powerlines). One day I was flying in rather poor weather. I wouldn't ordinarily have gone but I "had" to get to my destination 
. The only smart thing I did that day was plan to follow a river to my destination instead of going direct. The ceiling was quite low but the visibility was pretty good under the cloud....until all of a sudden the visibility dropped to less than a mile in a heavy rain shower 
. A quick 180 over the river got me going back the other way and a things got a little better a few miles later and I was able to make an uneventfull return back to my departing airport.
This happened along time ago but I still remember the incipient panic when I found my self low to the ground and could hardly see anything out the window.
All those elaborate diversion "systems" brief well on the flight school white board but the more complicated they are the less likely you will be able to do them when the chips are really down. In particular anything that requires significant head down time when you are diverting in conditions of poor visibility, can literally be deadly.
Finally the single most important thing you can do to increase safety when flying a cross country is to carry and know how to use, a GPS
. The only smart thing I did that day was plan to follow a river to my destination instead of going direct. The ceiling was quite low but the visibility was pretty good under the cloud....until all of a sudden the visibility dropped to less than a mile in a heavy rain shower . A quick 180 over the river got me going back the other way and a things got a little better a few miles later and I was able to make an uneventfull return back to my departing airport.This happened along time ago but I still remember the incipient panic when I found my self low to the ground and could hardly see anything out the window.
All those elaborate diversion "systems" brief well on the flight school white board but the more complicated they are the less likely you will be able to do them when the chips are really down. In particular anything that requires significant head down time when you are diverting in conditions of poor visibility, can literally be deadly.
Finally the single most important thing you can do to increase safety when flying a cross country is to carry and know how to use, a GPS
Avoid imitations
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My qualifying cross country was back in 1974. I flew Ipswich-Southend-Norwich-Ipswich with my instructor.
Two days later (4th Jan 1974, according to my now very tatty first logbook) I was briefed to fly the reverse route. I set off north from Ipswich to Norwich but encountered a suddenly decreasing cloudbase halfway along the leg. I knew there was a serious weather problem when I realised the top third of the Tacolneston masts were in the cloud (present chart gives them as 627ft agl, they might have been higher back then).
I realised I wasn't going to make it to Norwich so I turned back and flew towards Ipswich at well below 1,000 feet. I missed seeing the field, flying just to the east in decreasing visibility (easily done, it was just a grass field), but then found the estuary just north of Felixstowe. I turned northwest, knowing that I wasn't too far out. I was then given a steer by the helpful Ipswich ATCO and got back safely; I was the only one still airborne and by then the weather was quite dank.
At the ripe old age of 17 it didn't seem to be a big problem. My logbook just says "Qualifying X-Country. Aborted - Weather".
Two days later (4th Jan 1974, according to my now very tatty first logbook) I was briefed to fly the reverse route. I set off north from Ipswich to Norwich but encountered a suddenly decreasing cloudbase halfway along the leg. I knew there was a serious weather problem when I realised the top third of the Tacolneston masts were in the cloud (present chart gives them as 627ft agl, they might have been higher back then).
I realised I wasn't going to make it to Norwich so I turned back and flew towards Ipswich at well below 1,000 feet. I missed seeing the field, flying just to the east in decreasing visibility (easily done, it was just a grass field), but then found the estuary just north of Felixstowe. I turned northwest, knowing that I wasn't too far out. I was then given a steer by the helpful Ipswich ATCO and got back safely; I was the only one still airborne and by then the weather was quite dank.
At the ripe old age of 17 it didn't seem to be a big problem. My logbook just says "Qualifying X-Country. Aborted - Weather".
I've had 5 diversions/180s for real that I remember, 4 in planes and 1 in the heli.
The heli was serious weather - trying to fly a bay tour round the coast with the ceiling coming down and down. Finally when I was at 500' and getting close to the clouds I turned round. Problem was meanwhile the weather had come down along the route. Flew the coast at 500' and luckily there was still a clear passage over the hills further south. If not - would have continued to follow the coast and landed at another airport - or in the worst case in a field. Never a big deal in the heli.
Once in the plane for weather - no big deal, just decided it wasn't going to work and diverted. Diversion procedure: point plane in roughly the right direction, eyeball destination airport, fly there. Vis was poor so it wasn't trivial. I was still a fairly new pilot at the time and although I stayed calm I could feel how easy it would be to get worried. But I could always have got vectors or tuned the ILS at the diversion airport. (By the way this was Bakersfield with serious mountains fairly close by).
The others were aircraft issues - a couple of times when I got worried about the engine, and once when I noticed an inspection cover loose. None were a big deal nav wise, just pointed approximately at the destination airport using the Mk 1 eyeball.
One thing is ALWAYS have plenty of fuel. If you're low on fuel then it can quickly become a big problem. If you have plenty then ETA is completely unimportant.
Of course flight tests are different - though when I did my CPL diversion I just pointed in the right direction and used the thumb/finger/VOR-circle method to estimate distance, which my examiner was fine with. But I get the impression that these things are a lot more anal in the UK.
The heli was serious weather - trying to fly a bay tour round the coast with the ceiling coming down and down. Finally when I was at 500' and getting close to the clouds I turned round. Problem was meanwhile the weather had come down along the route. Flew the coast at 500' and luckily there was still a clear passage over the hills further south. If not - would have continued to follow the coast and landed at another airport - or in the worst case in a field. Never a big deal in the heli.
Once in the plane for weather - no big deal, just decided it wasn't going to work and diverted. Diversion procedure: point plane in roughly the right direction, eyeball destination airport, fly there. Vis was poor so it wasn't trivial. I was still a fairly new pilot at the time and although I stayed calm I could feel how easy it would be to get worried. But I could always have got vectors or tuned the ILS at the diversion airport. (By the way this was Bakersfield with serious mountains fairly close by).
The others were aircraft issues - a couple of times when I got worried about the engine, and once when I noticed an inspection cover loose. None were a big deal nav wise, just pointed approximately at the destination airport using the Mk 1 eyeball.
One thing is ALWAYS have plenty of fuel. If you're low on fuel then it can quickly become a big problem. If you have plenty then ETA is completely unimportant.
Of course flight tests are different - though when I did my CPL diversion I just pointed in the right direction and used the thumb/finger/VOR-circle method to estimate distance, which my examiner was fine with. But I get the impression that these things are a lot more anal in the UK.
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I've done two 180s as diversions.
First was lowering cloud, turned round, told the MATZ controller what I was doing, went back home
My mistake was not giving sufficient briefing to my passenger, who spent the return trip worrying about what would happen if we couldn't get back in where we'd taken off - the weather was coming from the north and this was an eastward flight with a return to the west. In fact I had a couple of alternates to the south in mind - my passenger said he'd have been happier knowing that at the time!
The second was considerably worse cloud than forecast (it doesn't happen very often, but it does happen), and I found myself much lower than planned with no space to go any lower and solid cloud ahead of me and to the left and to the right. A 180 got me out of it through a gap in the increasing cloud behind me, with reassurance from the nice man at Luton Radar (who didn't get very upset when I bust his airspace for a few seconds by going over one tiny cloud I should have gone under). No passengers that time - I don't think they'd have liked it!
First was lowering cloud, turned round, told the MATZ controller what I was doing, went back home
My mistake was not giving sufficient briefing to my passenger, who spent the return trip worrying about what would happen if we couldn't get back in where we'd taken off - the weather was coming from the north and this was an eastward flight with a return to the west. In fact I had a couple of alternates to the south in mind - my passenger said he'd have been happier knowing that at the time!
The second was considerably worse cloud than forecast (it doesn't happen very often, but it does happen), and I found myself much lower than planned with no space to go any lower and solid cloud ahead of me and to the left and to the right. A 180 got me out of it through a gap in the increasing cloud behind me, with reassurance from the nice man at Luton Radar (who didn't get very upset when I bust his airspace for a few seconds by going over one tiny cloud I should have gone under). No passengers that time - I don't think they'd have liked it!