Noise Abatement "Procedures" - Cause for Concern
 

At a general aviation airfield where I instruct from time to time it has become the custom to initiate the climbing turn after take off below 500 ft agl to avoid overflying a housing estate which, for reasons best known to the planners and local council, was permitted to be built a few years ago.

As a flying instructor teaching inexperienced pilots I am most concerned about this procedure since (often) the climbing turn has to be started circa 100 to 200 ft, depending on the environmental conditions. One could reasonably argue that perhaps operations should not be conducted from this runway with ab initio students but this would not really be practical.

We teach students never to turn below 500 ft in the normal course of events and yet in this case we turn a blind eye to this prudent restriction. Invariably I see pilots conducting this turn at 5 kts or so below the normal climbing speed at bank angles up to 30 degrees (spiral stability). Add a little turbulence and an engine failure and I feel we have all the ingredients for a stall/spin accident.

Nowhere in the UK AIP does it say that this procedure should be used although the club and aerodrome "flight order book" says that the turn should be initiated to avoid overflying the built up areas.

I am all for operating in a manner which avoids excessive noise for the locals but I am also concerned about the flight safety implications. Perhaps it would be safer over the long term to climb ahead to 500 ft beore turning although this would involve flight over the housing estate.

Finally, an exception to the 500 ft rule is when taking off and landing in accordance with"normal aviaition practice". I would argue that by turning significantly below 500 ft you are not complying with"normal aviation practice" and may therefore be in breach of the Act.

Despite the use of this procedure we still get noise complaints!!

Any comments?

Fireflybob:


A couple of questions.

(a) Is the built up area suitable for a forced landing after an engine failure?

(b) How many degrees of heading do you have to make to clear the built up area?

(c) Once you have changed heading to clear the built up area is it more suitable for a forced landing?


There is no great danger nor difficulty turning any aircraft below 500 feet above ground as long as you use a safe angle of bank and safe airspeed.

P.S.

CAUTION:

You should be high enough that you do not drag a wing on the ground during the turn. :D

Cat Driver:

a) No

b) 60 degrees

c) Yes

Turning below 500' does not breach the AIP. The AIP allows you to fly below 500' for take off and landing. It doesn't say that you have to be on a constant heading.

I was taught not to turn at any angle greater than 15^ when climbing.... I was also taught to turn at 60^ AoB at 250' on navigation exercises (with a bit more speed on, obviously)!!!

The FoB should read, words to the effect, avoid flying over the built up area by turning as soon as practically safe to do so. It could go on to list minimums for club aircraft, such as, min 250', max 15^AoB, min speed Best Rate of climb.

The FoB shouldn't make a pilot break the club rules to stay safe. It should give guidance on how to best achieve the goal.

The first question that should be asked is, is this an "official" noise abatement procedure. If its not in the AIP then it would appear that either it isn't, or the aerodrome have failed to notify it. Are Aerodrome Standards at the CAA aware of it?

For self protection the FOB should state that turns after take off shall not be commenced below 500 ft and with no more than 15 degrees of bank. Where a noise abatement procedure requires a turn below 500 ft, then further minima should be specified, to include Speed, an absolute minimum height and possibly configuration.

At a Midlands airfield the procedure calls for a 30 degree turn immediately after take off. The FOB should establish where Take-off ends i.e. not below screen height, ideally not before the end of TORA and not below a safe climb speed! If all these items are covered its about as safe as it can be.

I'm with Chuck here! Where does it say "never" turn below 500? Are you saying that you feel more comfy climbing toward a built up area that you say yourself doesn't provide any suitable place to force land? What if the machine you're flying has a poor angle of climb (ignoring the noise abatement issue) are you saying it's better to labour up to 500' before turning?
It seems resonable to fly in such a way so as to be able always to land somewhere 'soft and cheap' !

Dusty_B, the point I am making is that one is exempt from the 500 ft rule when taking off and landing in accordance with normal aviation practice. What is normal? Surely commencing a turn after take off at 100 ft is somewhat abnormal? It may be the safest course of action but does it comply with Rule 5?

nonradio, I agree that it does not says "never" turn below 500 ft but I am talking about what is desirable in the context of teaching ab initio students to fly. Expecting a low houred pilot to conduct this sort of maneovre is increasing the odds of loss of control which is far more likely to cause loss of life compared to climbing ahead "normally" and getting close to a few houses.

The arguement put forward so far make me think that we should not use this runway for departure for flying training.

FFB- my comment about 'never' was really a rhetorical question.
I also don't see how turning at less than 500' predisposes one to "increasing the odds for loss of control".
I do think that "getting close to a few houses" is not quite the attitude, however.
Maybe I just don't have as much confidence in machinery as you do...;)

Safety should be the prime consideration when training new pilots.

It is utter nonsense to believe that students cannot be taught to perform turns safely below 500 feet , altitude has no bearing whatsoever on safe turns.

If we are to continue teaching people to fly we will have learn to deal with built up areas encroaching on our airports. And the need to plan our circuits to best fit both safety and the noise question.

Cat Driver:

The closer you are to the ground the more vulnerable you are in an aircraft.

Introducing a turn at low height increases the probablity of loss of control when near the ground and therefore increases risk.

nonradio, you seem to be misinterpreting what I am saying

<Maybe I just don't have as much confidence in machinery as you do...>

I am not sure what you mean by this remark.

Firefly....

I am having difficulty following your reasoning.

If you are giving instruction to a student and the airport has a requirement to turn to avoid a built up area how can the student lose control of the airplane with you in it?

To use your reasoning you can not teach x/wind landings because it requires the airplane to be banked close to the ground, a shallow turn should not require any more bank angle than a strong /wind should it?

Anyhow I can understand not wanting to turn to a different heading during the departure close to the ground but once you are stabalized in the climb a shallow turn should not pose any danger.

Cat Driver:

Cat Driver

The issue is not when I am in the aircraft but when the student is flying solo, especially the early ones.

I note you are in Vancouver - I think the culture over here in the UK is somewhat different. The majority of instructors over here teach the crab method of cross wind landing versus wing down and anyway my concern is specific to departure not arrival.

Thanks for you input - I think we will have to agree to disagree on this one!

fireflybob:

There is nothing wrong with having different ideas regarding flying, as long as safety is not compromised that is the main thing.

I fly quite a lot in Britian and as to the x/wind thing I guess a lot depends on the type of aircraft and how you prefer to land will determine how much wing down you will use on landing.

One thing I could never figure out about you guys in Britian and that is the use of "on finals" seems strange to make a plural out of a singular. :D

Cat Driver:

Chuck

>One thing I could never figure out about you guys in Britian and that is the use of "on finals" seems strange to make a plural out of a singular. <

We don't have a call "on finals" in the UK. There is a call "Long Final" if ATC ask for it (4 to 8 miles from the runway).

The civil term is "Final" (singular), the military "Finals" (plural) for reasons best known to the powers that be!

FFB

'Fraid I will have to agree with Chuck AND yourself.

If you have concerns about your pupil's ability to cope with any task they can reasonably expected to cope with during their soloflight you should either:

1. Not use that runway for the operation

or

2. Keep the student under your wing a bit longer before soloflight from that runway

However I think that the majority of pupils will take something like a low level turn in their stride.

It surely will help them fly with greater accuracy if they have explained to them what the issues are.

Chuck:

Finals?
Trousers?
Scissors?
Spectacles?
Pants?

FD (NNS)

Fly: confidence in the engine keeping going over those houses!
If a pupil pilot or any pilot for that matter can fly a climbing turn at 501' he or she can do the same at 200'. I think I am objecting to the implied rigidity of your 'rules'. We're trying to produce pilots who can exercise judgement and be confident in their skills and it's clear that some instructors have a confidence issue themselves (cf reluctance to spin) or dwell on the dangers of flying beyond a healthy respect that can only communicate itself to the student perhaps to the detriment of his or her performance....
finally, some of us have always said "final" and the majority of instructors here don't teach 'crab method'.
The End.

I'm a brit instructor, and I teach the wing down unless the type requires the other.

I can see where FTB is coming from and also agree with Chuck.

The problem we have under JAR is a very pathetic requirement of slow flight and stall spin awareness. Therefore students can be left under exposed to the perils or not of flying by the seat of there pants. It is up to the instructor now to decide if he wants to dwell on this area or not. Some do, and some don't. if it was more a legal requirement, then we all would.
I am not suggesting FTB doesn't train students thoroughly in this area. I am also aware of the increased skill required of turning low level, particularly with a wind making this sort of turn become a downwind turn and the illusions it can produce.

Our PPL and in particular "NPPL" has become so sold as a licence that can be bought in the hours and on the cheap with reduced hours, is really giving the customer a false claim. It is also making the instructors job harder having to convince the student (customer) that he will have to spend more money to attain the skill required not of the licence but of the aircraft/field he has learnt from.

For example: Under the NPPL I believe it is a minimum of 1 hour for solo consolidation in the circuit after Ex14. What a load of tosh. Most students need around 3 hours to gain the confidence and "command" aspects of circuit discipline. What planet was the person on who made this sylabus? Fine, give them more instruction and hours solo, but so much for the advertised "cheaper" NPPL. How does that make the "School" look to its customers having sold them the package in the first place trying to be competitive to its neighbours?

I would imagine if my field had a turn requirement like that, I would need a few more sessions flying the turns b4 sending solo, as Chuck or someone suggested.
That customer is going to then whinge to his mates who learnt at airfield "b" that he took longer. What do you do?

Unless the CAA make a more stringent requirement to fly the aircraft rather than "operate" it, we would have a far more competant and confident new pilot in the sky. The CAA do seem to be forgetting what a good set of hands and feet can do in the cockpit. Loose the B**LS**T and fly the aircraft should be their next goal!

Capt. Airprox -

A bit of the thread I admit but if your "school" is selling a package offering any sort of license in the minimum time I would suggest that you are doing your students an injustice. All people learn at diferent rates and there is no way that you can guarantee to get everyone through in a set time unless you are prepared to cut corners.

Whenever I am asked by a casual enquirer or at the end of a trial lesson how long it will take to learn I point out that there is a minimum time but everyone learns at a different rate. Most people understand this and can relate it to their own and their friends experiences learning to drive a car.

This has a bearing on the low level turn discussion. So what if you have to take a few more sessions with them if at the end you turn out a more competent pilot. After all - if having been granted their ppl/nppl they then fly off to a different airfield on a cross country they can't refuse to follow a noise abatement procedure because there weren't any where they learnt to fly.

However, I doubt if it makes that much difference. The airfield at which I most often teach has noise abatement turns after take off on two of it's runways. As a result students are used to doing them right from their trial lesson and don't seem to take any longer to solo than they did before the procedures were introduced. Many airfields have different procedures to the standard rectangular circuit and it's just a thing they have to learn to live with.

Bob

There's nothing illegal about the procedure as published in the aerodrome manual, just needs a bit of prudence in its application. I can normally make 500ft in my trusty steed but I've got 50hp more than what you're teaching in. Possible solutions are teach short field / max climb from that particular runway and normal departures from the others. The other option is possibly for the airfield management to only use the other 3 runways unless absolutely necessary.

I do know that the phone gets VERY hot with complaints on a busy summers day. Maybe it's time for the users and airfield management to get together and have a rethink. 03 I suspect could do with being right hand for noise reasons.

At the end of the day there are more people in that estate that can complain I suspect than possible airfield users, and we have to be good neighbours. The turn before the houses I agree is not ideal, and can be risky for a low hours student. I think at the end of the day it's up to those of us qualified and able to operate as sensibly as possible so that if the students end up going further than the rest of us the 'perceived nuisance' is minimised, if not removed completely.

CM

Phew there seem to be a lot of issues flying around here!

Firstly, nonradio I don't care too much whether anyone teaches crab or wing down - as has been said it depends on the type to an extent but also I feel it's somewhat of a red herring in the context of the issue I raised.

ChilliMonster - would you please define (in the legal context) what you understand by "normal" aviation practice? It's a matter of opinion but all I am pointing out is that you may be contravening Rule 5 if you start a climbing turn at circa 100 ft. This is a LEGAL issue - it may be good airmanship to avoid climbing out over a housing estate but that is another matter! Perhaps a flying lawyer could comment on this? Naturally we should all operate to minimise the noise issue so long as flight safety is not compromised.

Nonradio, My comments may appear to imply a "rigid rule" but those who know me well know that this is quite far from the truth. Yes, I realise we live in the "real" world and that sometimes normal guidlines have to be modified to suit. What I am attempting to point out is that doing this on aregular basis is stacking the odds higher for some sort of incident.

What this all really highlights is the foolishness of building a housing estate near an active airfield, especially when objections were raised by the aerodrome operator.

I agree that it is quite possible to teach a student to fly a competent turn after take off commencing at 100 ft BUT we should be catering for the "lowest common denominator". In the event of an accident I could not, as an instructor, put my hand on my heart and say that we did everything we could to ensure it would not happen.

The more I see this issue debated the more I am of the opinion that in certain environmental conditions departures from this runway should not be contemplated.