Alister

Very good question. I haven't got any experience flying around mountainous terrain but I would assume under the circumstance you would put more focus on the artificial horizon. I would imagine in mountainous terrain you would get similar optic illusions to when you fly "VFR on top" - the attitude and bank of the aircraft is very misleading.

Chuck Ellsworth

There are many airplanes that have no artificial horizons and are flown in mountainous areas.

Therefore we must go back to basic training to determine how one maintains a constant angle of bank and altitude turn in that environment.

For sure the answer does not lie in using an artificial horizon.

Are you an instructor ?

I am asking so as not to get into an unnecessary argument as it serves no useful purpose.

Cows getting bigger

Not that I have ever been in such a circumstance, I would offer that engine RPM (and therefore airspeed) is key in such a scenario.

mad_jock

Chuck when you learned what was the normal level of experience of the instructors?

ProfChrisReed

I found Chuck's question an interesting one, because I can't work out the answer.

I've instructed turning on gliders, but only in the flatlands. There, the horizon is pretty uniform.

I've flown in hilly areas, and there I fly the turn by feel, with regular checking on the ASI to ensure that I've not been fooled by the horizon playing fairground tricks on me. The closer to the hill, the more I check.

I'm not sure how to translate this into teaching - maybe in a powered a/c with a shallow angle of bank, monitoring the ASI would do the trick? But in a glider at, say, 30 degrees of bank @ 50 kt turning 360 degrees twice per minute, I'm not sure that would do it for a student. No A/H, and although the yaw string is better than the ball for slip it tells you nothing about angle of bank or attitude.

My guess would be to teach the turn, prompting as required, until the student gets the feel for steady angle of bank and airspeed (probably judged by airflow noise in a glider), and then teach monitoring the ASI for checking purposes.

Chuck's answer would be interesting.

[BTW, I don't currently instruct, and only used to instruct at the introductory flight level, in case anyone takes this post as an indictment of UK glider instructor training.]

172_driver

Probably not...

Instructor's level of experience is not much more than the student's. I think the aviators of your time were highly skilled if you compare.

mad_jock has a valid point. When I did my CFI their was lots of emphasize put on fancy maneuvers like Rectangular Course Patterns, S-turns, Turns Around a Point (for Private) but not much on basic flying skills. Simply I believe the instructors are not taught how to teach basic straight & level, turns, climb/descent .... Moreover, in the Private syllabus (e.g. Jeppesen) Slow Flight, Steep turns, Stalls (Secondary, Accelerated, Cross-Control, Elevator Trim) and Simulated Emergency Approach & Landing is introduced at flight 3 and 4. Probably the most useless syllabus ever created!!!!!!! The syllabus we use in a Part 141 approved course is a little more generous, but still at flight 5 our students are supposed to fly at MCA within 100 ft. Recipe for disaster!!

The way I was taught, IIRC: Flight 1. Effect of controls 2. Straight & Level 3. Climb/Descent 4. Turns 5. Climbing/Descending Turns ..... I wasn't doing any accelerated stalls at 60 deg. AoB at least.

DFC

That yaw is the secondary effect of roll. It happens because at 30 degrees angle of bank the aircraft will slip and the resultant change in the direction of the relative airflow on the fin/rudder causes Yaw.

If you were flying an aircraft which was simply a wing and rolled the aircraft with the ailerons (elevons!!) to 30 degrees AOB and the C of G was exactly central etc then the aircraft would again slip but there would be no yaw because there would be no fin/rudder and no keel surface aft of the C of G etc.

In the UK is it still possible to obtain a licence with as little as 15 hours training.

The answer to your question however lies more in the situation of society ( and insurance companies as well as authorities) being more risk adverse and no longer accepting the loss rate / accident rate / injury rate that was associated with aviation in the 1950's. Not to mention the fact that we have learned from our mistakes!!.

The effect of high(er) terrain is covered during the operation at linimum level part of the PPL course because at 500ft MSD, even quite small hills disrupt the true horizontal.

It is not just terrain that causes problems. Over flat terrain the horizon is clear, flat and true and some 75nm away at 5000ft ASFC.

If the visibility is 9600m the visible surface ends some 4nm ahead of the aircraft when on the surface and less than this at 5000ft.

Take a student up into the clear sky over a 8/8 stratus overcast. Note well the attitude for S+L then take them back down into the 5k below and ask them to select the exact same attitude and see what happens. The aircraft now descends because they have put their "horizon" (the limit of visibility) on the same spot. This is an issue when operating in reduced visibiity as the pilot will often tend towards descending by following a false horizon.

This makes the altimeter scan quite important so ensure that the desired altitude is being maintained.

It also makes the basic technique for selecting an attitude come into focus;

Select - select the attitude

Hold - hold the attitude steady

Adjust - if the aircraft is not doing what is desired then Select a better attitude and repeat the process.

The same applies in a turn a quick glance at the altimeter and then back outside tells the pilot if the aircraft is maintaining altitude.

Having said all that for turning in a valley a few things should be remembered;

1. A climbing or descending turn will use up less horizontal ground space than a level turn.

2. As in other cases, a partially full water bottle provides a horizon reference when straight and level and in balance. Use the bottle to determine some reference features on the opposite side that are at the same level.

3. Strat the turn on the downwind side of the valley and turn into wind. This also decreases the size of the turn.

In other words - get onto the downwind side of the valley. Select a few features for reference on the other side and start the turn. If you start descending then this helps so long as a safe level above the hard bits is being acheived.

--------

172_driver,

The difference is simply a teaching method.

one is more trial and error than the other.

trial and error in a controlled environment can work. However, it requires a very attentive instructor and can have problems with "primacy" i.e. the students first method that achieves the aim is very hard to change becuase their brain associates that method with the successful outcome even if it is worng in your eyes.

The european system lends itself to a building block teaching style where early exercises are short and relatively simple and the length / complexity of exercises increases with experience. Early diagnosis of learning rate and progress as well as bringing a very disciplined approach to flying. (don't confuse disciplined with lack of fun!!).

The US system uses a less disciplined approach which can work with the right students but has problems in that the student can become overloaded as well as making determination of progress difficult except at ket stage points.

Thus the origin of the European system in the military with it's associated chop points compared to the US civil system where the student is more left to spend their cash for as they choose as long as they are having a good time even if they never make progress.

Chuck Ellsworth

I probably shouldn't stray from the turn discussion but DFC's comments regarding the teaching methods in Europe compels me to ask a question that truly puzzles me.

If the teaching methods are so refined in Europe why do so many training aircraft damage the nose wheels and firewalls due to landing on the nose wheel first?

mad_jock

All the nose wheel incidents I have personal knowledge of were all with Instructors on board of less than 500 hours total experience.

Some of the explanations of what happened were hilarious. Most of them showing that the instructor didn't have enough spare capacity to see situations develop never mind react to the student doing something unplanned and outside the box of the instructors experience.

I would love to see the breakdowns of nose gear incidents by school and instructor experience. Willing to bet 50 quid towards Help for Hero's that the schools with ex mill QFI CFI's who run thier schools with a toe up the arse of instructors who don't teach the correct way have a lower than average (if any) incidents.

172_driver

DFC,

Thank you for a very informative post. I agree with the way you put it. Today I had a few students, practicing glide, slip and MCA on there fifth flight with a completion standard of "Altitude +/- 100 ft, Airspeed +/- 5 kts and Heading +/- 10 deg". I felt horrible having to do this!!! They are not comfortable with basic climb/descent, turns, climbing/descending turns (incl. rudder handling, trim and attitude flying) yet. Very hard to determine there progress under such circumstances. Oh well...

Alister

Yes I am an instructor and you are quite right in saying some aeroplanes fly across mountainous terrain without Artificial Horizons, especially many years ago. If you have one though it will definitely help you.

As well as an AH you may also have a turn co-ordinator, altimeter, ASI and compass. If you ever get a vacuum failure and your AH and DI fails you will need to rely on these 4 instruments for both turning and straight and level flight when you cannot rely on a visual attitude.

In a turn you can also use "stick and rudder skills". It is possible to sense the angle of bank of your aircraft by the feedback from the ailerons. By applying a pre determined amount of back pressure you can keep the aircraft in level flight.

Hope this helps

Chuck Ellsworth

Hope this helps.

Actually it is confusing me more as I thought we were discussing how to turn an airplane using outside reference aided by verification of some instruments.

When turning an airplane in conditions where the outside reference does not have a normal horizon I have always relied on the indications of the altimeter as a conformation that I am maintaining level flight in the turn. ( maintaining a given altitude. )

I have not mastered the skill of being able to determine attitude by " feedback from the ailerons ".

Maybe I need to improve my stick and rudder skills?

ProfChrisReed

I've looked back at my earlier post and realise that I misread Chuck's "altitude" as "attitude".

Isn't the real problem with training in hilly areas the problem of teaching how to maintain a constant attitude? If the nose is constantly moving up and down in relation to the (notional) horizon, maintaining altitude is very much a scondary consideration it seems to me.

My assumption (without personal experience) would be that, by reference to visual indicators outside the cockpit:

a. Maintaining angle of bank is a lesser difficulty even with a hilly horizon, but

b. Maintaining constant attitude must be really difficult for a student.

If I'm correct, how is maintaining attitude taught in those circumstances?

An experienced pilot will maintain attitude by the feel of back pressure on the controls, monitored by regular reference to the ASI. Are students taught the same way?

It seems to me that altitude must be a secondary consideration until the student has got these two nailed. Losing altitude could be caused by failure to add enough power (if bank and attitude are maintained constant), or by allowing the nose to drop which could be caused by insufficient back pressure on the controls (steady bank), or increasing bank (steady back pressure), or a combination of both.

What's the trick to teaching turning in the hills?

Chuck Ellsworth

Lets pick this apart one bit at a time.

First off using " Feel " of pressure on the controls is a very poor indicator to maintain a constant altitude during a turn, assuming your intent is to maintain a constant altitude during the turn.

What I do before I roll the airplane to the angle of bank I plan on using is look at the picture out the windshield to see what it looks like in level flight by referencing the terrain I am looking at, I check the altimeter as I roll the airplane to the bank angle I want and monitor the altimeter as my primary instrument for level flight during the turn.

Using the airspeed indicator as the primary instrument will result in a roller coaster pattern of altitude control in the turn due to airspeed indicator lag which will result in constant pitch changes caused by chasing the air speed indicator needle.

Brian Abraham

A very worrying statement, particularly coming from an instructor if you don't mind me saying so.
You have the skills in spades Chuck, what I see is you begging for a pole of something tailwheel and radial powered for the sake of currency/proficiency.

generalspecific

Roll 90 degrees and pull to the buffet? ... or am i missing something

OneIn60rule

Show the 30 degree bank.

Then teach how to maintain the 30 degree bank.

Lookout, Attitude, Instruments (Altimeter, Ball)


Thereafter ask them to stop the turn.

Then teach how to enter.

Etc..

DFC

Every procedure in the world is based on rate 1 or 25 derees bank whichever requires the less bank.

If dealing with CPL and IR students 30 degrees as a maximum is standard SOP with commercial operators (for a good reason).

The traget AOB for initial medium turns should be 25 degrees when a suitable margin above the stall exists and 15 degrees when less margin is available eg while at climbing or gliding or approach speed. This concept translates into all future aspects of flying that the student may do. i.e. remember - Primacy!

The rationalle between AOB and stall margin can be well demonstrated during the stalling / spin avoidance exercises.

This basic exercise can then be further expanded in a later post solo exercise by explaining the rate 1 turn and the relationship between AOB and speed to acheive rate 1 which leads into turns using the magnetic compass / timed turns.

If 30 degrees is the traget AOB then most PPLs and CPL students will vary from say 25 - 35 with sometimes 20 to 40 being seen at times (based on visual attitude flying). 45 is a steep turn under JAR-FCL.

At the appropriate stage, turns at 45 degrees AOB can be covered and after that point, the student should be capable of turning at any AOB up to 45 degrees while also demonstrating the use of a suitable margin above the stall plus passenger comfort aspects as appropriate.

Remember that 15 degrees AOB is rate 1 at 80Kt and 25 degrees is rate 1 at 180. Most basic trainers climb at 80 Kt or thereabout so 15 degree bank is not far from rate 1. At 100 Kt rate 1 is 17 degrees. So using 25 degrees in a basic trainer is turning quite a bit above rate 1.

Dudley Henriques

As an aerobatic instructor you become VERY tuned in to control pressures and coordination, and this transfers back all the way to primary basics.
My opinion on teaching turning is to introduce it early as a visual reference maneuver and keep the student outside the cockpit. There's plenty of time to get into instruments as you progress past the basic coordination involved with turns, and visual cues are best introduced initially to help the student recognize proper turn entry and exit coordination.
Medium turns using medium bank are the optimum tool to use in introducing turns as the aircraft is more stable in that range with little underbank and overbank.
Use the HORIZON as the T&B indicator and NOT the T&B indicator on the panel. The nose of the aircraft will instantly show the student the quality of the turn entry and exit from the turn, as adverse yaw is instantly visually apparent using this visual cue.
Let the student experiment with aileron and rudder as they watch the nose, after you have explained that for the entry to be coordinated, the nose will be pinned on the horizon during the roll into the turn. Demonstrate a PINNED entry to a medium turn as you keep the student's eyes solidly on the nose of the aircraft. Demonstrate both excessive rudder and inadequate rudder for the aileron you are using both entering and exiting the turn and allow the student to see the resulting slew of the nose on the horizon resulting from lack of proper coordination. Demonstrate the need for increased angle of attack to manage the split lift vectors you discussed with the student BEFORE YOU TOOK OFF!
Let the student do most of the flying. NEVER take over the controls a second longer than absolutely necessary to demonstrate technique. Also keep the 'Theory discussion" limited while in flight. Do the theory on the ground before flying dual with the student, then discuss it again after the flight. What's key is letting the student fly the airplane while you correct and guide.
This is important! Use medium turns to introduce the student to turn. It's in medium banked turn where the student can handle the learning curve for control pressure and coordination most easily.
Once comfortable with medium turns and the student's using the nose on the horizon as the visual cue and handling the medium turn well, THEN introduce shallow banked turns and steep turns with the underbank, overbank, and increased back pressure these turns require.
Hope this helps a bit.
Dudley Henriques

Chuck Ellsworth

Hey Dudley....