Over-pitching

What Is Over-pitching?

Over-pitching

Overpitching occurs when you demand too much power from the engine and a drop in Rotor RPM (RRPM) occurs. When you keep raising the collective lever without any consideration for power limitations; you are increasing the pitch angle of the main rotor blades. As the pitch angle is increased, drag is also increased. To overcome the drag, more fuel must be added to the engine to increase power. This is normally done by a correlator or a governor or both.

If the collective lever is raised further, at some point the engine will be at full throttle. Any further attempt to raise the collective will result in a reduction of RRPM as the engine has no spare capacity to overcome the drag on the blades. This is a very dangerous situation. “Overpitching”.

As the RRPM decays, the main rotor blades will cone more and the coning combined with the reduction in RRPM and subsequent loss of lift (due to reduced airflow over the blades) will cause the helicopter to descend.

A pilot’s automatic (but INCORRECT) reaction to stop the descent is to raise the collective. Obviously this will increase the pitch angle and cause a further reduction in RRPM and a faster rate of descent.

Recovery From Over-pitching

The recovery from over pitching is not instinctive and relies on good training habits. When the low RPM warning horn/light comes on during normal flight, you must react immediately.

  1. Lower the collective to reduce the pitch angle and thereby reduce the drag on the main rotor blades.
  2. Simultaneously open the throttle to help recover the RPM.

Combining the collective movement with the throttle movement will recover the RRPM in a timely fashion.

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Basic Autorotations

Basic AutorotationsDuring your helicopter training, you will eventually have to learn how to glide the helicopter in unpowered flight. All helicopters can glide. We call it “autorotation“. We practice autorotations so much in the course of training that they become a part of normal helicopter flight. But do not think that autorotations are common in real life. Engine failures are extremely rare and tail rotor failures are even rarer. So how do we do a basic autorotation?

Your instructor will probably do all the throttle work as you will not have to use the throttle in a real emergency. Check with your instructor as to what the verbal warning will be before commencing an autorotation.

Basic Autorotations

  1. Make sure that you are in straight and level flight. 80 knots and 2000 feet above ground level (agl) is a good starting point. Look outside at the horizon and make sure that you take note of where it appears to cut through the windscreen (your reference point). When you perform part 2 in this list, count to 3 before you look inside at any of the instruments.
  2. Lower the collective lever fully down. This is the most important thing to do in any autorotation. When you feel the collective hit the bottom stop, raise it up again approximately 2.5cm (1″) to prevent a rotor over-speed. As you lower the collective lever, the nose of the helicopter will try to drop due to the change in airflow over the tailboom. This must be prevented by use of the cyclic. The nose will also try to yaw dramatically to the left (in most helicopters – check with your instructor). Prevent this by adjusting the pedals.
  3. As mentioned in 2 (above), as you lower the collective, the nose will drop. We do not want this to happen. In fact, we normally want to make the nose come up a little bit to help restore rotor RPM. Therefore you need to come sufficiently aft with the cyclic to achieve a nose up attitude. This will also slow the helicopter down to autorotation speed (normally 60 – 70 knots).
  4. As the nose yaws left, put in sufficient right pedal to keep the helicopter pointed straight ahead. This requires a lot of right pedal due to the large reduction in torque. If you have done this correctly, the helicopter should remain in trim (balance). NOW YOU CAN LOOK AT THE INSTRUMENTS inside.
  5. We are only interested in 3 instruments:
  • The Air Speed Indicator (ASI)
  • The tachometer for rotor RPM
  • The slip indicator.

The main thing to remember is that you should not look inside as you are moving all of the controls. Look outside and count to 3 after you feel the collective hit the bottom stop. As long as you keep the helicopter speed steady, the rotor RPM will also remain steady. If you find that you are doing 90 knots and you should be at 60 knots, smoothly move the cyclic aft to reduce the speed. If you do this quickly, you could over speed the rotor system. Also, if you find the speed has reduced to 50 knots, smoothly move the cyclic forward to increase speed. If you do this quickly, you may get a rotor underspeed. Do not chase the needles. Look outside at the horizon to maintain your attitude and thereby maintain your air speed.Remember that when you move the collective, it takes about 3 seconds for the rotor RPM to change. If the low RPM warning horn or light comes on, lower the collective slightly and check that the RPM is recovering.

Basic Autorotation Recovery

To recover, your instructor will open the throttle and provide power to the rotor system. He will tell you when to begin the recovery. To commence the recovery, smoothly raise the collective up until you reach the normal climb setting for your type of helicopter. Check the temperatures and pressures. Make sure there is NO traffic around you (especially above you). With a little practice you will find that you will become quite proficient at basic autorotations.

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EASA Air Law For The PPL

Updated on September 24, 2016

Under EASA regulations, the syllabus for the Air Law theory for PPL students has changed considerably. All of these changes have required Approved Training Organisations to rewrite their training material. To date, there are no books to teach the new EASA regulations in Ireland.

For this reason, I have written a book specifically for PPL students (fixed wing and rotary) to give them the required knowledge to pass the EASA Aviation Law examination. The book covers everything listed in the EASA requirements for this subject.

For a FREE PREVIEW – Click Here

Please leave a review if you get a chance as it will really help me sell the book. Reviews really make a difference and I would be very grateful.

“EASA Air Law For The PPL – Air Law For The Irish Pilot” can be purchased using the link below:

BUY HERE

 

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How to Progress Your Career

Updated on 24th September, 2016

Helicopter Preflight

Introduction

Almost invariably I get asked the same questions on every course that I teach. When I run a commercial course, the CPL students will at some stage, almost always ask me “What do I have to do to get ahead in the helicopter industry?” or words to that effect.

In my opinion this is an easy question to answer and actually pretty easy to achieve if you are prepared to work hard.

What You Need to Do

So what do you need to do to progress your career as a helicopter pilot?

Well you actually do not have to do very much. You only need to do what you were trained to do. I will provide a list below of what I think is important. I would expect all helicopter pilots to be able to do the following.

  • Never be late.
  • Arrive early enough to work so that you are not rushing to get your preflight tasks completed.
  • If you perform the daily preflight checks, make sure that you take your time and do them properly.
  • Take your time when completing paperwork – accuracy is important.
  • Keep up to date with changes in legislation or operations etc.
  • Dress appropriately.
  • Fly accurately and to the best of your ability.
  • Offer your assistance to anyone who needs it.
  • If you have nothing to do, look for small jobs that you may be able to do.
  • If you have a problem, try to think of a solution before running off to report it.
  • Think about the “What if” scenarios. Have a “Plan B”
  • If you make a mistake, put your hand up and accept responsibility.

The list is not conclusive and I am sure there are plenty of other items that could be added to it. But if you can manage to consistently do the things on the list, then that is all you need to do. Without doing anything else you will get noticed. People appreciate hard work. You will get noticed for being consistent and for being a hard worker. All employers love hard workers.


Putting it into Practice

I tell my students that they should be striving to achieve everything on the list but that they can do more. They should aim to be the best pilots that they can possibly be. Perfection is unobtainable but that is what you should strive for. You should aim to be better than all of the other employees in the company.

Being better does not mean only flying better. Of course the flying skills are important but there is so much more to it than that. Your expert knowledge will also set you apart. It never ceases to amaze me how many CPL pilots coming through to do the Flight Instructor (FI) course, who have big gaps in their theoretical knowledge. Gaps in subjects like Air Law, Meteorology and Principle of Flight are common because they have not looked at a book since they obtained their CPL.

If you want to be different, refresh your knowledge. Become an expert in your field. Let people come to you for the answers because they know that you have the knowledge. You have the answers. Of course you will never be capable of knowing it all. No one can achieve that. But you can know more than anyone else if you put your mind to it.

Conclusion

Therefore what you need to do to progress in the helicopter industry is be the best pilot that you can be. Learn as much as you can about technical matters, relevant legislation, meteorology etc. And generally work as hard as you can and help out as much as you can – all while being a nice person to work with.

Do not try to step on other peoples shoulders to make it up the ladder. This will come back to haunt you in years to come. Just by keeping your head down and helping others while doing your job to the best of your ability is guaranteed to get you noticed by the right people.

Let me know if you think this was useful by leaving a comment below. Thank you.

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