Saturday, 23 November 2013

Twice as nice


As you can see, we have been cursed with a spell of typical English weather that has temporarily halted all flying. I thought I'd take the brief respite to write about our latest challenge — flying the twin engine Piper Seneca.

Compared to the small single engine planes we have flown to date, the Seneca is a bit of a monster. It has nearly three times the power of the Warrior and flies 50% faster. There is a lot more equipment on board, like de-ice systems and autopilots and though a lot of it does not work, you at least get the feel of a 'real' aeroplane. I could — in theory — fly home in one of these.

You couldn't call our battered old examples glamorous or smart, but with a bit of imagination and a bit of a squint you can picture a couple of wealthy executives in the back being whisked off to their next meeting by, well, one of us. No longer are we just learning to fly ourselves around, suddenly there is the reminder that we are training as professional pilots. It won't be long before we will be piloting large and very expensive aircraft with paying passengers in the back. Scary.

Buddy at the controls looking forward to his first flight
I had been somewhat nervous about the additional weight, speed and complexity of the Seneca, but after extensive briefing and memorising lots of new check lists I finally got to try it out this week. I was first out of our group, so it was up at 4.30am to check in and complete the pre-flight checks.

Once we were all strapped in I took my time running through the unfamiliar before take-off checks before I finally got to say for the first time "starting no. 1 engine". Taxiing was tricky, with the rudder pedals connected to the nose wheel via springs only, and my progress to the run-up area was cautious and less than elegant.

The power checks in the run-up area revealed the first, and really only tricky part of operating the Seneca — the twin throttles. They are quite sensitive and moving them together while keeping the same power coming from each engine is far from easy. Unlike the Warrior, you can't just shove them to full either. The turbochargers will kick in too strong and "overboost" the engine, damaging it.

Onto the runway and line up, two quick check lists then it was time to release the brakes and open the throttles. The acceleration was rapid, much more so when the turbos kicked in. Between the vague nose wheel steering and inability to keep the throttles balanced my take off roll meandered all over the place, but almost before I had time to sort it out we were doing 77 knots and it was time to fly.

As soon as we were in the air, I could feel how stable the plane was and just how rapidly it climbed. No time to think though, there was the after take-off check list to get done before turning at 500 feet — which takes all of 35 seconds in this plane.

More knobs, buttons, levers and dials than you could shake a stick at.
The instructor was certainly right when he said it loves to climb. Levelling off was a challenge at first, each time I thought I had the plane nicely trimmed out at the right speed I would look away for a moment then find myself 100 foot higher. I'm not sure if it is turbo lag or something, but it really takes a while to set get it properly set up.

Once it was settled down it flew beautifully with minimal input from me. It was far less affected by rough air or thermals, and felt like it would hold its height and heading until it ran clean out of fuel. This would not take long, as it drinks about 22 gallons of avgas per hour. Not one for the environmentalists!

It took a while to get used to the constant speed props. No longer is the power set by choosing a engine speed, instead we set the pressure of the fuel/air going into the engine. The plane will automatically twist the propeller blades to keep the engines turning at the same rate, regardless of your speed through the air or the amount of power set. We are used to listening to the engine note for speed changes, so it is disconcerting to hear the same drone all the time. We also have to carefully tune the engine speeds to avoid irritating 'beat' frequencies.

We spent some time getting used to the plane and doing general handling practice, then it was off to Goodyear to fly some circuits and landings. The big moment! Rumours abound about how difficult it is to land, and how it will just 'fall out of the sky' onto the tarmac before you are ready.

Perhaps it was simply the quality of the instruction, but I didn't have a problem. Certainly the control forces are higher than we are used to — it's definitely a two-handed job to flare — but much to my relief I was able to set it down quite nicely each time.

We were doing "touch and go" landings, so the next part happened very fast. There was just time to retract the flaps and fiddle about trying open the throttles evenly and stay more or less straight when we were back to rotation speed and it was time to fly again. Around we went, another five circuits, each time I got a bit better with the check lists, but I never quite got on top of the touch-and-go checks.

Then it was time to literally fly home. The fun parts of having so much speed on tap is beating all those Warriors back to base!

Asymmetric flight


One of the nice things about the twin is its symmetry. The single engine aeroplane may look symmetrical, but its engine and propeller only rotate in one direction. This gives rise to all sorts of complicated effects that conspire to pull you off course to the left, and constantly varying amounts of right rudder are required to keep it straight.

On the Seneca, the engines rotate in opposite directions and everything is nicely balanced. You hardly need to trouble the rudder at all. Provided, that is, both engines are running.

Err.. shouldn't that propeller be, er, going around?
But barely had we got to grips flying with two engines when it was time to fly it one just one.

Pretty much all twin-engine planes can fly on a single engine, though with reduced performance. This is great because it means an engine failure does not necessitate an immediate landing, and you are allowed to fly out of range of suitable landing areas.

So much for the theory, actually flying with one engine is quite an experience. When an engine fails, the plane will veer off course, start turning towards to the dead engine, lose around three quarters of its power and descend.

Once back under control, the rudder forces to keep the plane straight can be huge, literally all my strength was needed when flying slowly at high power (think take off!).

The worst time an engine can fail is of course just after take off, so this is what we practice. We will get a few hundred feet in the air when suddenly the plane will lurch off one way or another — the pesky instructor has closed one of the throttles and covered them up so you can't see which.

We then have to control the plane, identify the failed engine, run through a whole load of extra check lists and fly the circuit with one leg jammed on the rudder. Just before the landing the instructor will return control of the 'dead' throttle for landing.

The scary part in a real engine failure is called the committal altitude. Once you have the landing gear down and the full flaps out, the single remaining engine simply does not have enough power to make you climb. You HAVE to land. There is no going around and trying again!

That's all for now. We are enjoying flying the twin but the pressure is really on. If all goes to plan, in around  two weeks I will be a qualified commercial pilot with a multi engine rating. Keep everything crossed for me!

2828L - the first twin engine plane I have flown.

Sunday, 17 November 2013

Farewell little Warrior...



It was quite an emotional day today — my last ever flight on the single engine Piper Warrior. Just a pleasant cross-country jaunt to make up the fifty hours "pilot in command" time required for the commercial pilot licence. It was an entirely uneventful flight on a lovely day, with a few clouds around to add interest and pretty up the sky and plenty of time to reflect on how far we have all come in the last five months.

Once our class have finished with them in a few weeks, the Warrior fleet will be sold off, replaced by the more modern Archer. Some of them have been in continuous use for flight training with the same school for over thirty years and it's a sad day to see them go

That flight was also the last time I will ever pilot an aircraft alone, at least in a professional capacity. From now on I will always be flying with an instructor or examiner or ultimately with a line captain in the other seat.

On Monday we start on the Seneca twin engine aircraft, a faster and much more complex beast. The training schedule is very intense with several hours flying per day for the next few weeks, leading up to our commercial pilot licence exam and twin engine rating.

And then at long last home to cold rainy England to see my family, friends and my wonderful and very patient wife. I miss you all.

The best part so far? Easy. Aerobatics in the Extra hands down.




Friday, 15 November 2013

Upset recovery training

Flying "under the hood"
I've just returned from progress test four*, our last exam in a single engine aeroplane. The whole test is "under the hood" meaning I could see only the instruments and not outside. After performing various basic manoeuvres, stalls and slow flight the instructor simulated a vacuum pump failure by covering up the artificial horizon and heading indicators with scraps of paper.

Using this limited panel of instruments, I demonstrated timed turns, which are done by flying an accurate rate of turn for a calculated time to end up heading in the required direction. Next I had to recover from "unusual attitudes" using just the limited panel instruments.

In this context, unusual attitudes are pretty tame, the nose will generally be within 20 degrees above or below the horizon and the wings within 45 degrees of bank.

An aeroplane can of course fly as much as 90 degrees nose up or down (straight to the sky or straight to the ground) and up 180 degrees of bank (upside down). This is the full range of attitudes that is actually possible, but normal training we are exploring just four or five percent of this envelope. In commercial aviation, it is even less.

So if we never experience the more extreme attitudes, how do we know how to react if we suddenly find ourselves in one? The answer is to strap in tight to a fully aerobatic stunt plane with a massively experienced instructor and do some...

...Upset recovery training


In three days of flying the awesome 300bhp Extra 300L fully aerobatic plane in all sorts of crazy attitudes and situations with APS training we were able to explore what happens way beyond our normal limits, both in terms of flying and what our stomachs could take! I should add that we were still nowhere near the limits of the aircraft, these things can take plus or minus eight g which is a lot more than I can.

So what is an aeroplane upset? Any time you are outside your normal operational limits for pitch, bank and speed, for whatever reason, you are obviously in an upset.

Less obviously, any time the plane does something you did not command on the controls, or does not do something you did command, it can be said to be upset. Most likely this is because you have stalled, but it could be a jammed or disconnected control surface or some other mechanical failure.

A stall occurs when the "angle of attack" — the angle at which the air hits the wing — is too great. It has nothing to do with speed, though trying to fly too slowly can certainly cause one. You can stall at any speed at attitude if you try (or if you don't pay attention) simply by pulling back too much.

We practice gentle stalls on our school Warriors regularly, and the results are an unspectacular nose drop, perhaps accompanied by one wing falling a little. The recovery is easy and equally undramatic. They are slow, stable, draggy machines designed to be easy to fly for students and amateurs.

Many aircraft do not do this. For example fast, slippery aircraft with thin swept back wings like the ones we should be flying in a year or so. In these machines, the stall can be sudden, violent and leave the aircraft in almost any attitude and falling fast.

One answer is simply to say "these aircraft shall never be allowed to stall," and go ahead and fit stick shakers, stick pushers, envelope protection and other funky gadgets to prevent the pilots being so stupid. But to err is human, and people are still dying because pilots lose control of even ultra-modern airliners because they stalled.

So this is what an Extra does if you stall it from a slipping turn. A slip, by the way, is a perfectly valid technique where the rudder is applied opposite to the bank angle. This makes the plane fly somewhat sideways, increases drag and increases descent rate. Very useful if you need to get down fast or fix a too-high approach to landing. A slip is a stall-resistant manoeuvre, look how hard I have to work to make the plane stall:

video


Look fairly dramatic? Compare this to a stall from a skidded turn. A skid is NOT a valid manoeuvre. A pilot will typically skid when trying to get around a turn faster using the rudder instead of banking over more. Reacting incorrectly to an engine failure on a twin engine plane can cause a skid too. Unlike the slipping turn when I really had to pull hard and ignore the plane shaking and complaining, this one had no warning at all...


video

If this happened on final turn, even with the excellent training we have just had, there is no room to recover before meeting the ground. The only answer is to fix it before it happens. We were told how to spot the skid (the slip ball moves to the high wing) and not to hesitate to fix the situation straight away, whether we are pilot flying or not. That's a lesson I won't forget in a hurry.

APS teach a fantastic recovery technique that's now drummed firmly into us; push, power, rudder, roll, climb. It works in almost every situation, even if you don't know how or why you got there. But there is one mode of flight where it will not help you — that is the fully developed spin.

This next video shows what a full spin looks like. We try various controls movements to escape, but as you can see none of them help and some make the spin faster. The only recovery that does work is the one I take at the end of the clip, although I fluff the calls a bit. Well, wouldn't you?

video


You can't see the altimeter very well in this video, but from the spin entry to when the instructor says "recover" we lose 4000 feet in 34 seconds! During the recovery I lose a further 1500 feet though I did better on subsequent attempts.

Being able to recover visually is one skill, but imagine you are flying happily along in the clouds when out of nowhere there is a thump and you are suddenly upside down. Panic? Freeze? Flail around on the controls? A week ago I'm sure I would have done something similar. But now...

video

That video shows the instructor using a snap roll to simulate the effects of wake turbulence — flying into the vortices left by a plane in front of you. I am under the hood here, eyes closed, not touching the controls and expecting a typical unusual attitude recovery. I manage to recover from violent inverted upset on instruments in only a few seconds. I am not trying to show off here — I am trying to show how invaluable this training really is.

Enough of the serious technical stuff. Part of the training is simply taking the fear out of being in unusual attitudes, having a "face full of dirt", and what better way to desensitise than trying our hands at some aerobatics?

Here is my first (and second) attempt at a Hammerhead. Sometimes incorrectly known as a stall turn, you pull vertically upward until you have almost run out of airspeed, then kick the rudder to rotate the plane sideways into a vertical dive (see picture on the right).

Sounds awful, but the whole thing happens close to zero g (yes, like in space!) and it is actually quite a gentle experience for the pilot until the pull-out at the end.

video

I also managed to fly some reasonable loops, Split Ss and Cuban 8s. To fly a Cuban 8 you do the first three-quarters of a loop,  roll back the right way up, pull up into another loop and do the same thing again. The full range of bank and pitch attitudes in a single manoeuvre.

video

Certainly not air show quality stuff, but I am very happy to have tried it.

If you have been to an air show recently, you may have seen a stunt pilot doing a vertical climb followed by a crazy tumbling manoeuvre. This is the Lomcevak (Czech for 'headache'). The plane is flown vertically until almost stationary, then some violent control input I don't understand causes it to do a gyroscopic precession around the rotating engine-crankshaft-propeller assembly. Or something. So when the instructor offered a demonstration, how could I say no? This one is certainly not gentle on the pilot or the plane!

video

It just remains to say a big thank you to the amazing staff at APS. All you pilots out there, private and commercial alike, think seriously about getting some upset recovery training like this. It may be expensive, but it might just possibly save your life and others too.

Before you go, please do consider donating a few points to the very worthy but under-sung causes of prostate and testicular cancer through my Movember page. I haven't quite made it to £100 yet, but even so, here it is at 14 days as promised. Pretty pathetic but I will keep trying...



* I passed by the way

Sunday, 10 November 2013

Hold it!

Have you ever wondered how your holiday jet is able to fly thousands of miles with no sight of the ground, descend into the clouds, manoeuvre around, hold, approach the airport and pop out of the bottom of the clouds at exactly the right place, speed and height to land?

The Buckeye VOR DME C hold and approach
pattern used in our training and tests
You might think GPS has something to do with it, and computers and of course autopilots. But no.

Instrument approaches pre-date all of those, and the essentials are simply the basic flight instruments, a nearby radio beacon, a radio instrument to pick it up and a printed chart of the approach procedure known as a plate.

And a lot of practice.

On the right you can see an approach plate, in this case to Buckeye Municipal Airport which is a tiny little public strip near our old base in Goodyear. This is a reasonably complicated plate, and there is a lot of jargon, but it is not as bad as it first looks.

The main part is simply a drawing of the procedure seen from above. It's not drawn to scale, but just gives the general picture. You arrive from wherever you like and fly to the little round symbol in the middle, which is a radio beacon. Then, you fly round and round the racetrack pattern until you are ready to approach and land. Next, you fly off five miles to the north west, descend a bit, turn around, descend a bit more, go back over the beacon and finally descend and head in the general direction of the runway on the right.

Underneath is a side view of the same approach, you can see that each part has a specific altitude. There is also a table that give the lowest altitude you are allowed to fly to as you approach the airport. If you still can't see the runway at this point, you must do the missed approach procedure. In this case, turn around to the left, climb, go back to the beacon and start flying round and round again.

A radio magnetic compass. This model has two
needles, which track two different kinds of
radio beacon. Here, the plane is heading north. There
is a beacon off to the left and slightly behind, and another
ahead and just to the right.
The clever part is this whole procedure is defined and flown using just one radio beacon. In the aircraft the we have an instrument called a radio magnetic compass (RMI). It has a needle that simply points to the beacon, and around the outside is a compass card that rotates to show which way the plane is heading. Add in a stopwatch, and provided you remember to reset it every time you cross the beacon you can now pinpoint your position.

Sounds easy enough, but regular readers will have already guessed the next part... it's not that simple. Firstly, we are flying a plane with sole reference to the instruments, taking care of radio communications and performing various check-lists at the same time. Secondly, interpreting these basic instruments is not easy. And thirdly there is the wind to make the whole thing even more confusing.

Probably the most difficult part of the procedure is entering and flying the hold — the little race track pattern in the middle. A hold is simply a way to get an aircraft to stay in the same place for a while (aircraft, unlike every other vehicle ever invented, are physically unable to stand still.) It's something we are practising a lot at the moment.

Three ways to enter a hold, depending on
the direction you approach the beacon.
The hold always starts at a radio beacon, and it is defined by the compass direction (track) of the straight part heading towards the beacon. This has to be flown for a specific amount of time, usually one minute. Then the pilot turns — usually right — using a standard rate turn (three degrees per second), flies on the opposite heading for a minute. Another turn to the right and in an ideal world they are back on the inbound track one minute from the beacon.

The wind can make a right mess of this. If there is a cross wind component, you can correct for it on the way inbound by flying whatever heading keeps the needle pointing to the required ground track (the one on the plate). But to do this, you do need to get onto the correct track pretty early so you have time for the trial-and-error procedure required to find the heading. Confused? See blowing in the wind.

On the other three parts of the hold — the outbound leg and the two turns — you have no beacon to track to and hence no point of reference. In theory, if you needed a certain amount of correction on the inbound leg, say 5 degrees left, then you should need three times this amount on the outbound leg but in the other direction — 15 degrees right. This is because the wind is blowing you off course during both turns as well as the outbound leg, a total of three minutes of wind needs to be accounted for.

An early attempt at the Buckeye hold on a windy day.
You can see the strange shape of the turns caused
by the cross wind, and also where I got confused
and applied the wind correction the wrong way on one
of the circuits. The red blob is the beacon. The
wind appears to be from the south east here.
Head or tail wind components muck up your timing. In order to get the required one minute inbound, you have to adjust your time outbound. Again, it is trial and error though you do have some idea what to expect before you start from the winds aloft forecast. These are the purple numbers I have scrawled on the plate.

What you should end up with, after a few circuits, is a kind of egg-shaped pattern with the into-wind turn being tighter than the down-wind turn, and the outbound leg skewed to connect them together. What we tend to end up with is a right mess that looks like someone just dropped their knitting.

There is a lot more to it than this... there is the entry to the hold to get right, there are various 'gates' that are used to monitor your progress around the pattern and so on. I won't bore you with the whole lot, if you would like to find out more, here is a good explanation.

I have a couple more lessons to practice this on Monday before yet another progress test. Following this I have one final solo. That will be the last time I fly a single engine aeroplane on the course, as the following week we start on the Seneca. Apart from having two engines, it is fitted with retractable gear, variable pitch propellers, superchargers and flies about 50% faster than the Warrior. Twice as many knobs and levers and a lot less time to think!

I am also doing the APS upset recovery training course next week which should be an eye-opener. They use aerobatic Extra 300 stunt planes to explore all sorts of crazy flight attitudes and conditions from inverted to spins and of course how to get out of them.

It's going to be quite a week.

The next challenge; getting to grips with the Piper Seneca

Friday, 1 November 2013

Cross Country Qualifier and Movember

Cross Country Qualifier

On Tuesday I was able to squeeze in my cross-country qualifier when a schedule change unexpectedly freed up a day. There's a massive amount of planning required as it essentially counts as three separate trips, so I completed as much as I could the night before and caught the first bus at 4.30am to complete the rest at school.

Tuesday was far from a typical Arizona autumn day — in fact it was more like a typical UK autumn day. Temperatures were relatively low which is a good thing, but so was the cloud which is not so great. At times the cloud base was forecast down to 6000' or even 4000'.

But the interesting part was the winds, which at 6000' were forecast at 24 knots (about 28 mph) and the surface winds looked strong and gusty to the south. A few months ago I would have not attempted to fly. I knew it would be challenging, but I was (just) within my limits on all the forecasts and provided there were no delays, I would be technically good to go. All I had to do was persuade the duty instructor! I finally succeeded, but it took half an hour and put me even closer to the out-of-limits surface winds forecast at Ryan.

There was no chance of cruising at my planned 8500' on the way to Ryan due to the cloud, and even 6500' was close. I was using the flight following radar service as usual, but as I got near to Ryan, Tucson Approach started to direct me to different headings and altitudes (radar vectoring) rather than just monitoring me. That was new.

A Cessna landing at Ryan
As I approached to land, Ryan tower reported the wind at 21014KT20 which in English means 16 miles per hour gusting to 23 miles per hour and coming from the south-south-west.

The runways at Ryan point 240 degrees or south west — 30 degrees off the wind direction — meaning I had a 10 knot cross wind and a 20 knot head wind. Bang on my maximum. Happily though the landing went really well on the first attempt, and I quickly refuelled and got back into the air before the winds got any worse, fairly confident that conditions were better to the north.

The next leg out to the west was even more interesting. The strong cross winds meant I had to take some dramatic correction angles — up to 25 degrees — which looks very odd. You point the plane one way, and actually fly in an entirely different direction! As I approached the familiar Table Top Mountain, there was a series of text-book wave clouds, long parallel sausage shapes.

Unfortunately they were well below my altitude, forcing me to descend to about 4000' to get clear below. I radioed Albuquerque Centre to let them know I was descending, and they promptly terminated my radar service, which was not the outcome I was looking for! Not their fault though, below about 5000' they simply can't see us on their radar.

A TCAS (traffic collision avoidance system) similar
to the type not fitted in our aircraft.
As I turned north again towards Goodyear, the weather steadily improved and the winds dropped making the rest of the flight uneventful. I felt quite nostalgic to be back at the now quiet Goodyear. Time for a quick lunch break, more fuel, and back in the air for the final leg.

This too was a busy flight. The cloud had pushed everyone down to similar altitudes making the practice areas very busy. Without any technical wizardry to spot other aircraft in our vintage Warriors, we rely on look out and radio calls. 4500' was just so popular that in the end I chose to fly an unconventional 4300' just to give a bit of extra safety margin and was scanning like a crazed owl.

After 300 miles, landing at three airports and five hours in the air, I was back at Falcon, tired but happy. Job done. Strange to think that, professionally, that was my last ever solo. If I didn't fly privately I could work until I was 65 and pilot an aircraft alone again.

Movember

A Hair-O-Plane, yesterday.
This blog has had — amazingly — over 21,000 hits to date. Clearly there are a lot of people out there who enjoy reading it, not just friends and family. I'm hoping to persuade you all to part with just a little tiny bit of your hard earned cash for a very good cause; it's Movember!

Yes it's that time of year when we grow ludicrous facial hair in an attempt to raise some cash for vital research into key men's health issues including prostate and testicular cancer.

I know, growing a moustache hardly compares to running a marathon or doing a six-minute-mile in Death Valley in midsummer dressed as Darth Vader, but hey it's not as easy as it sounds.
  1. It's against the school uniform code
  2. I am going to look stupid for a whole month
  3. My wife hates the idea (she will be paying for me to shave it off)
  4. It will probably be ginger
So have a heart and bung me and my team a couple of pounds. For each £100 I raise I will release a photo of my progress. You have been warned.

Go on, it only takes a moment. Thank you!