View Full Version : Safety alt. -what do you teach?
27th Nov 2000, 00:26
Just wondering what others teach on VFR safety alts. Most people seem to teach 1000' above highest as per IFR, this is fine if pilot is going to climb up into it if in trouble but a student/non IMC rated PPL should not be even cosidering this, and 1000' seems too high if you are looking for when to start thinking about turning back/selecting a field etc.
27th Nov 2000, 13:30
I teach the IFR MSA as a start point - but make it clear to the student that it's not mandatory and that if necessary they can go lower than that subject to the low flying rules.
I also point out that while it's perfectly acceptable to go lower than the IFR MSA - they need to be aware of what problems that may cause them.
For things like this, where the law or standard safe practice doesn't cover it, I think that we should make them think about it themselves and possibly point out a few pitfalls than they may not have been aware of - then it's up to the student.
It becomes pretty obvious during the training flights if they're not going to be sensible about it.
29th Nov 2000, 11:16
What, pray, is a 'VFR Safety Altitude'? Under VFR you're responsible for your own collision and terrain avoidance; hence your minimum level is as defined by the requirements of Rule 5 and your maximum level probably by either regulated airspace or cloud.
As I understand it, the reason why instructors (sensibly in my view as a punter) teach VFR pilots to decide on a safety altitude stems from recognition of the vagaries of visual navigation.
Imagine the low-time VFR pilot pressing on towards a lowering cloudbase (I know that he shouldn't but he might). He knows that there is a height obstacle near his track. What if he gets off track? This might bring him too close to the high point. If he has remembered his MSA, he should know when he ought to divert, rather than continuing on into what may be a dangerous situation. I was always told to allow 500 feet over the highest point within 5 nm of my intended track.
When doing the low-level nav exercise, it was pointed out to me that features with vertical extent, such as TV masts, become more useful than railway lines etc, provided that you don't fly right up to them and get snagged on the guy cables. As always, you have to comply with the low flying rules and exercise judgment dependent on the specifics of the situation (even if that judgment is to light up and fly at low level and around the villages, as in the low level navex). It seems to me that noting an MSA on the chart for each leg of the intended xc flight can be a useful aid to making judgments en route.
[This message has been edited by FNG (edited 29 November 2000).]
30th Nov 2000, 23:52
Safety Altitude relates only to IFR Flight. VFR pilots should be aware of the ground elevation and any obstacles in the vicinity. Visibility is another important aspect, if it is low you need to think even harder about the terrain, especially if the cloud is low.
Remember High ground, Low cloud and Low vis do not mix with VFR operation
If you start teaching safety altitude to pilots who are not qualified to fly IFR you are in danger of encouraging them to climb into more trouble than they are already in. JAR-FCL philosophy is TURN BACK, or don't go in the first place.
1st Dec 2000, 02:18
Right on the nail,BEagle.
MSA is purely for IFR flight. Rule 5 is the main consideration in the equation, provided that you have adequate visibility and clearance from cloud and CAS.These are dictated by the Visual Flight Rules as laid down in the ANO.
1st Dec 2000, 03:23
'VFR Safety Altitude'? I've never taught a VFR safety alt - apart from Night VFR, which has a similar requirement to IFR safety alts.
VFR is just that: Look ahead & determine if legal (&/or safe) separation from both cloud & ground is feasable.
If not go elsewhere.
Oh, and always have an escape route so you can escape before you're r ooted.
Art E. Fischler-Reisen
2nd Dec 2000, 03:38
What are the "vagaries of VFR navigation"?
They weren't taught in my time.
2nd Dec 2000, 20:17
Have a damn good look at the Met before you go and if there's any doubt either don't go in the first place or plan a different route. When airborne turn back or divert around the weather in good time. Non IMC qualified pilots should not be taught to climb to safety altitude. What if they get stuck above cloud?
I think that what my instructors (three of them, with very different styles, but they agreed on this) were getting at was not that johhny ppl should pick a height and assume that it's a safe height whatever the conditions, nor that he should climb up to a certain height, even if this puts him in cloud, above it, or into a scud-run, but instead that he should be mindful that if he finds himself forced by cloud below a certain height, that, even if he is still legal, this should be a pretty clear clue to him that he ought to turn back or divert.
He may think that he is on track, but what if he has carelessly failed to hold an accurate heading, forgotten to align his DI and compass, or been drifted off by a wind stronger than forecast and not yet appreciated this fact? That tall tower 3 miles south of the nice line drawn on the map may in fact be looming up ahead. I recall a dual navex where the cloud ahead of us turned out to be a lot, lot lower than the Met checked immediately before departure indicated. So the conversation went:
Wrinkled Sage: "lung glasshopper, what your altitude?"
Grasshopper: "Honolable Master, altitude is xxxx"
Sage: "and what your mininum altitude for this leg?"
Grasshopper: "yyyy" (xxxx minus not v much)
Sage: "Ah so, what you do now then?"
[Long pause, painful sound of brain working incredibly slowly]
Grasshopper: "er.... divert"
Sage: "fuggin-A right, let's geddoudahere"
I think that the point that they were trying to get across was that, whilst it is probably impossible to teach judgment, it is possible to teach bases upon which judgments may be made.
Art E. Fischler-Reisen
6th Dec 2000, 03:11
Frying by number.