Sunday, January 27, 2008

Common problems with loaned general aviation headsets

Ever since I joined the Redcliffe Aero Club in March last year, I’ve been borrowing a headset each time I went flying. The club has a number of basic headsets that students can use for free during lessons, most of them of the Altronics brand. They are regularly maintained and even replaced, and they usually do the job.

I grew a bit frustrated with those headsets over the last few months though. The most common problem I experienced was with the mike boom not staying in place correctly. The mike book is the part of the headset that connects the microphone to one of the ear cups. It is usually either a hinged wire frame assembly or a flexible metal tube that can be bent so that the microphone sits just a few millimetres from the lips (the so-called “flex boom assembly”). What happens over time is that screws on the wire frame get loose, the flex tube develops a tendency to move back to its original position, or the linkage between the mike boom and the ear cup comes apart and pops out, leaving the mike boom dangling.

As a result, the mike invariably ends up moving away from my lips, which means that people on the receiving side of my radio communications experience a fainter voice and a lot more noise, i.e. a very badly degraded signal-to-noise ratio. So that’s all not very optimal.

Typically, with such a faulty headset, I would need to use my left hand to push the mike closer to my lips when making a radio call. This is not ideal in the circuit since the best practice is to make calls during turns and not after or before. This is to maximize the chance of other aircrafts sighting us. Other pilots will look for us when they hear the call (“turning base”, “turning final”, etc.), and they’re most likely to see us if we maximize the cross-section of the plane that they can see, i.e. if we are banked.

Therefore, with one hand holding the mike near my lips, that leaves only one hand for the yoke, throttle, trim and flaps. In most cases this works fine since flaps, throttle and trim are set before or after the turn. But you get the idea. It seems wrong to have my left hand busy with the “communicate” thing while both hands could be used for the “aviate” thing. In addition, it is quite disruptive when trying to have a conversation with the instructor. Try that when adjusting power in a turn and you’ll realise you need to grow a third hand. Or get your own headset.

There are a few other problems I’ve found with headsets that have seen too many hours, too many students and too many planes. On one occasion, I had one of the two jack plugs slightly come out of the socket. That was the thick one, the one connected to the speakers in my headset. I think it was helped by my right knee nudging against it, but I also suspect it was caused by wear and tear of the plug. As a result, the instructor could hear me, but I couldn’t hear him. It happened during the roll on a touch-and-go, and I realised something was wrong when Mal reached for the carby heat and firmly pushed it in.

The story was that we were practicing crosswind circuits and I had forgotten to remove carby heat on final, most likely because I was busy with all those things that keep you busy in a crosswind final. After I applied full power for take-off, Mal shouted “carby heat, carby heat” at me but I couldn’t hear him, and I can understand he got a bit cranky on this one as the end of the runway was approaching. On the climb-out we sorted out what the problem was and realized the plug was a few millimetres out.

Another thing that happened to me during training lessons was that the headband came lose and changed position in flight. Before each lesson I took time as part of the pre-flight routine to adjust the headband and make sure it felt comfortable with my sunglasses on. Still, one ear cup would drop at some point, which would force me to hand over the controls to the instructor while I was putting the headset and my sunglasses back in place. Not the kind of thing you want to be bothered with when you’re trying to make the most of a training flight.

Comfort is another problem with “best value” headsets. Last September I went on a one-week air safari from Redcliffe to Ayers Rock, for which we spent about 30 hours in the plane. I’ll talk more about this trip in future posts. For the time being, let’s just say that after 4 to 5 hours in the plane each day I had the impression that the headset had grown spikes that were slowly making their way through my skull. Granted, I do not have much hair to offer as a cushion between the headset band and my skull. But still, a nice cushion around the headband would have been nice.

So, little by little, I made up my mind about buying my own headset sooner rather than later. I had in mind to buy one after I got my GFPT as a gift to myself, so why not now rather than in two months? According to what I heard and read, proper GA headsets can last decades if properly taken care of, so delaying that purchase did not make sense. I ended up buying a pair of David Clark H10-60 which I find absolutely awesome. This post is getting a bit long now, I’ll go through the details of the selection and purchasing process in the next post.

Saturday, January 26, 2008

Steep turns and compass turns

Now that I have demonstrated sufficient proficiency in crosswind landings to be allowed to fly solo to the training area, I can get on with the other remaining lessons for the GFPT.

According to the Redcliffe Aero Club syllabus, I still need to do compass turns, precautionary search, maximum performance circuits and two hours of instrument flying. Plus a couple of hours of solo airwork in the training area. If everything goes according to plan, I should be able to get all that done within the next two weeks. Fingers crossed.

On Wednesday I went back to the training area with Lee to practice compass turns and steep turns. I had already done one session of steep turns two months ago. What I remembered was that steep turns with 45 degrees angle of bank were no big problem, not really different from a 30 degree turn really. There was however a lot more difference going from 45 to 60 than there is from 30 to 45.

At 60 degrees I really had to pull the control column all the way back to maintain a constant altitude in the turn. The acceleration experienced in the frame of reference of the plane is 2 G. I could feel the skin on my face, especially the cheeks, being pulled downward. In one turn I tried to raise my right hand and it really felt twice the weight. I know, this shouldn't come as a surprise, but as always it's one thing to read it in the book and another thing to experience it in the plane.

This time it all went a bit more smoothly then the first time. I did well at maintaining altitude within the required 100ft margin for a full-circle steep turn. This despite the fact that the horizon was hard to find on that day. Lee noticed that I didn’t wait for the nose to start falling before pulling the control column, I’ll try to work on that when I go solo. We also discussed how much power to add in steep turns in order to keep a good safety margin between us and the stall speed. I was not consistent enough however with rolling out within 10 degrees of the target heading, so that’s also something to work on.

Compass turns were rather uneventful. As long as you remember the ONUS (Overshoot on North and Undershoot on South) and SAND (apparent turn South when Accelerate, North when Decelerate) rules that apply for the Southern Hemisphere, then it’s just practice.

The nice thing in Redcliffe is that because of the 07/25 orientation of the runway, the compass error linked to acceleration is very obvious when accelerating on take-off. With the nosewheel on the centreline for a take-off on 07, the compass swings well past East in the few seconds after applying full power.

It probably is also quite obvious when decelerating during a short-field landing, but keeping the plane going straight while braking keeps me busy enough to not have had the opportunity to stare at the compass so far. What's also quite likely is that on landing the various shocks and vibrations will prevent an accurate reading of the compass.

Lots of flying booked for the next weeks. Getting up at 4:45 twice this week was hard, but I’m happy I did it. Booking lessons within a few days of each-other really helps with not loosing the feel for the plane, but that may turn out to be a costly habit in the long run :-)

Wednesday, January 23, 2008

Crosswinds tick!

Some absolutely awesome flying was had yesterday morning. At 6AM the windsock was showing a strong crosswind from the south, so I took off with Lee in BUQ, the other Cessna 152, for a session of crosswind circuits. This was pretty much the same drill as last time, using runway 07 with a strong crosswind from the right, just with no rain.

In the pre-flight briefing we had decided to use only 20 degrees of flaps and aim for 75 knots on base and 70 on final. Crosswind landings require a lot of rudder and aileron work, and these 5 extra knots make a real difference when the moment comes to swing the nose of the plane back onto the centreline and keep it there while flaring.

The other advantage of an increased airspeed is in reducing the angle of attack required for creating a given amount of lift, which increases the margin between our angle of attack at any given moment and the angle of attack at which stall happens. This is particularly important in turbulent and gusty conditions, such as this morning, since a sudden change in airflow direction could stall one wing, or both, which is a sure recipe for disaster at a few hundred feet above the ground.

On the base leg I applied myself to maintaining 75 knots and controlling our rate of descent so as to end up between 600 and 700ft when turning final. The reason behind that is to ensure that we are established on final not below 500ft. This is not an actual regulation, but more of a best practice to make sure we have enough time to get ourselves sorted out on final.

This is not really hard in fact, just a matter of concentrating and maintaining the proper scan between the runway, the ASI and the altimeter. One reason why you want to really stick to the airspeed of 75 knots in the Cessna 152 is that Vfe is 85 knots. It only takes a gust of headwind and a couple of seconds of inattention for the airspeed to reach the end of the white arc.

My landings this time were a lot better than the time before. I was careful to really fly the plane all the way down. I only flared too high on one occasion today, which is a definite improvement over last time too. Lee suggested that I removed the crab as I crossed the fence, i.e. way earlier than in my previous session. This worked wonders.

Doing so gave me enough time to transition properly to the wing-down technique after removing the crab and make sure I was tracking along the centreline before starting to flare. After flaring I forced myself to give the plane enough time to float above the runway and decide itself when to touch the ground. This was no problem since I could control track and heading with rudder and aileron. On a couple of occasions I could even distinctly hear the upwind main wheel touch the ground before the other one (and before the nose wheel), which is very rewarding.

In total I did five good landings, and as a result Lee gave me a tick for crosswinds. This means I can now go solo to the training area over Bribie Island. Actually, I already went solo there about a month ago, but that was early in the morning on a day with no wind, either actual or forecasted. I still need to complete about two hours of solo airwork before being able to attempt the GFPT test, which is still scheduled for February 29th.

During one circuit this morning a Cessna Caravan called inbound from above Brisbane International control tower as we were turning onto the crosswind leg. Lee called him and proposed to extend our downwind leg to let him land first, which the pilot of the Caravan gladly accepted. On late downwind the Caravan called a short base turn. I looked over my left shoulder and could see the Caravan in a tight descending turn that clearly indicated there weren’t any passengers on board. This was a Caravan from Seair Pacific, a Queensland charter operator based on the Gold Coast. A few minutes later it made a departure call for Lady Elliot Island, which is about 50 nautical miles north-east of Bundaberg, in the top right corner of the Brisbane WAC chart.

Tomorrow morning, weather permitting, we’ll go to the training area to practice compass turns. This is again a 6AM-8AM booking, which means getting up at sparrow’s fart for the second day in a row. But flying in the early morning has this way of putting a smile on my face for the rest of the day, so I really cannot complain.

Wednesday, January 16, 2008

More crosswind landings and a shutdown blunder

Last Friday I went flying in the early afternoon. The cloud base was definitely above 1000ft, but wind was a concern. As usual when bad weather is forecasted I rang the club before leaving home. Mal asked what I intended to do, I said crosswind circuits, which he was happy to hear since that was pretty much the only thing on the menu in Redcliffe on that day.

We did six landings on runway 07 in the course of 1.1 hour. I did the first one, then Mal demonstrated the second one, which was of great help, and I did all the other ones. We had rain from time to time but not much, and certainly less than the last time.

Before taking off we discussed where the wind would be coming from on all legs of the circuit, and what that would mean for our angle of climb or descent and how we would counter drift in each case. The wind was a south-easterly, which gave us a crosswind coming from the right on take-off and on final.

After lining up I turned the ailerons into the wind to prevent the wind from lifting up the upwind wing during the take-off roll. A few seconds after leaving the ground the plane started to weathercock into the wind. It is a good thing to let the plane turn into the wind a little to counteract the crosswind and track along the extended runway centerline, but not too much otherwise you’ll end up flying straight into the wind!

On the crosswind leg we had a tailwind and therefore an increased groundspeed, which made our angle of climb shallower. As a consequence, it was not possible to reach 1000ft before turning downwind, so I turned downwind at about 800ft and kept climbing.

On downwind the wind came from the left and had to be offset by pointing the nose to the left of where I wanted the plane to go. The turn to base gave us a headwind, which meant that I had to add a bit of extra power to get a lower rate of descent while maintaining an airspeed of 70kt. Mal had me look at the ground to better realize how slow our groundspeed was, and indeed the ground wasn’t moving very fast.

We made the turn to final in such a way as to end up on the upwind side of the extended centreline, i.e. to the right in our case. I pointed the nose to the right of the runway and crabbed it all the way down. I managed to maintain the final speed of 65kt reasonably well.

Prior to entering the plane I had discussed with Mal my initial idea of removing the crab ahead of time in order to not have to do too many things at the same time. He didn’t recommend it, saying it was something that would come later with experience, rather than a useful technique to learn crosswinds.

I did a couple of good landings, and even one where the upwind wheel touched the ground before the other main wheel, followed by the nose wheel. OK, I also did a landing when all three wheels contacted the ground at about the same time, which was less good. And even one where, according to Mal, I was very lucky not to have the tail hit the ground.

I faced a number of problems on that day that need fixing if I want to be able to land safely in strong crosswinds. They’re more or less all related to the timing of the flare.

The first problem was with keeping the nose down and maintaining the 65kt airspeed all the way down final before the flare. I would start to pull the nose up slightly at about 100ft which could potentially bring us dangerously close to the stall speed. My normal scan on short final is to go back and forth between the runway and the airspeed indicator. I think I spent too much time looking at my position with respect of the runway because of the crosswind and didn’t notice the airspeed decrease.

A related problem was that I flared too high on almost every landing. I don’t really understand why, since I had managed to get the flare consistently right in the past on landings where the crosswind component was negligible. My guess is that after I removed the crab I was concerned with not letting the airplane drift downwind, which is why I hurried the landing sequence by flaring too early. Not that it would have made the plane touch the ground any earlier of course.

After landing and clearing the runway we taxied back to the apron making sure to turn the ailerons into the wind. During the shutdown checklist I did one of the most stupid things I have done so far in an airplane.

When doing the magneto check before turning off the engine, I turned the key one notch too far to the left when selecting the right magneto, i.e. to the “off” position. I realised immediately what I had done and turned the key all the way to the “both” position. The engine ran rough for a second or so and then returned to normal. This in itself was no big deal, and is even a normal part of the shutdown sequence on some aircrafts. It is known as a dead-cut check and is supposed to check that the grounding of the magneto switch is correct, i.e. that no magneto is live after shutdown. A bunch of people with a lot more experience than I have discussed the pros and cons of the dead-cut check on

What was really stupid is that I got distracted by this small incident and carried on to switching the engine off using the key, just like a car. The normal procedure is to starve the engine of fuel by bringing the mixture control to the aptly named idle cut-off position. The engine of course eventually stopped after I realised my mistake and pulled the mixture control all the way back. But for a few long seconds the engine made unhappy noises. Maybe it was just fatigue at the end of a demanding hour in the air, but if that’s the case that’s worrying, the flight is only over when the engine is shut down. I still feel upset at myself for doing such a stupid thing.

In summary, some progress made on crosswind landings, but more work still needs to be done, especially on safely controlling the aircraft in the final stage of the landing. Keep the nose down when the runway is approaching, maintain that 65kt airspeed, remove the crab and then flare normally as I would do on any “normal” landing.

Sunday, January 6, 2008

Clouds, rain and demanding crosswind landings

I went flying on Friday. Sort of. At lunchtime the reported wind in Redcliffe was 15 knots with a crosswind component of about 12 knots, much better than the days before. Still quite close to the 15 knots crosswind limitation of the 152 though, but the wind was expected to fall in the afternoon, so there was a glimmer of hope that I would go flying.

I called the club and Scott, one of the new instructors, said that if I wanted to come over we could go do some crosswind circuits. That sounded like a plan, so I grabbed my flight bag and drove to Redcliffe. Soon after I hit the Bruce Highway the rain grew very strong. I spotted a car in the ditch at the Redcliffe exit ramp which looked like it had spun out of control after taking the turn too fast.

It was a full house at the club since no-one was flying. Lots of new faces on the other side of the counter too since the club hired quite a few new instructors recently. I said hi, grabbed the folder for VH-IVW and went to pre-flight the plane under light rain. Everything was in order with full tanks, so I went back inside to fill in the sign-out sheet and soon Scott and I made our way to the plane.

Right after leaving our parking spot I tested my brakes and the left main wheel skidded on the wet tarmac. We taxied for runway 25 and couldn’t hear anyone on the CTAF frequency at all, even though it is shared between the aerodromes of Redcliffe, Caboolture and Caloundra.

Soon after take-off it became clear that we were heading straight into one of the numerous dark fractostratus clouds that were hanging around the aerodrome. Scott said we’ll be doing 500ft circuits today instead of the normal 1000ft so as to stay clear of clouds. That sounded like a very sensible idea. Scott said he had been to Maroochydore in the morning and at some point the cloud base was as low as 400ft.

On the first circuit my downwind leg was a bit too far, I doubt I could have glided back to the runway in case of engine failure. The crosswind final was OK, I had no problem maintain my track along the extended runway centreline. I had a bit of trouble removing the crab and lining up the plane with the runway on short final though, so Scott jumped in and gave me a hand with the flare and rudder work.

On the second circuit my spacing was better. On downwind I was flying parallel to the runway and in the direction of the marina at the tip of the Redcliffe peninsula. I tried to maintain exactly 65 knots on final which helped with the landing flare but I didn’t put enough right rudder in, so here again Scott had to jump in. As soon as the nose of the plane was pointing down the runway again, Scott handed the controls back to me. Heels on the ground, flaps to 10, ailerons into the wind, full power and soon we were airborne again for our third circuit.

The rain grew a lot stronger on the crosswind leg, and by the time I turned downwind it was pounding the poor 152. The rain was coming in from the sea and reduced our visibility to the point that I could only see the tip of the peninsula as a darker shade of gray through the rain. As we passed abeam the threshold of runway 25 Scott decided to take over the controls and perform a full stop landing. The cool thing is that I could witness a textbook crosswind landing. During the flare Scott kept the height of the plane constant with lots of small pitch adjustments. We touched on the upwind wheel first, then the other main wheel, then the nose wheel. Just like it says in the book :-)

All in all that was only .4 of an hour spent in the air but I don’t regret going. That was my first time flying in such poor meteorological conditions. I started my training last March, at the end of the Australian summer, so I’ve had mostly very pleasant conditions so far. Only once last year did I have to cancel a lesson because of the weather.

I spent the next half-hour at the club booking lessons for the next month and a bit. I had to reschedule my GFPT pre-test and actual test because the weather won’t allow me to finish all the flying before the end of January as originally planned. The test is now scheduled for February 29th, which hopefully will give me ample time to prepare.

I realised that I still need to do a lot of work on crosswind landings. Parts of my problem today was due to the fact that I removed the crab too late, which meant I had to do too many things at the same time: straighten the nose with rudder, roll the wings into the wind while at the same time keeping an eye on the airspeed, controlling the flare and checking for drift.

What I’ll do next time is remove the crab a lot earlier, say when I pass 200ft and remove carby heat, so that hopefully I will have the longitudinal axis of the plane nicely aligned with the runway centreline and drift countered with aileron by the time I start the flare.

I have a lesson booked for next week Thursday. If the weather ends up as forecasted it’ll be a crosswind lesson again. My objective is to fly well enough so that the instructor will not have to take over at any stage. Let's see how we do on this one.

Tuesday, January 1, 2008

Double Bummer thanks to Crappy Queensland Summer Weather

We’ve been getting pretty crappy weather in the coastal areas of Queensland for the last couple of weeks, and it doesn’t look like things will get better anytime soon. Not only did the weather conspire to shorten our holidays last week, but it will most likely mean the cancellation of my two flying lessons planned for this week.

So if I can’t fly I’ll do the next best thing, blog about flying. And if I get really desperate I’ll resort to going solo to the training area in CAVOK conditions using the flight simulator at home.

About a week ago we left Brisbane on well-deserved holidays to the other side of the tropic, yet still in Queensland. We flew to Mackay in a Jetstar A320 then made our way to Airlie Beach in a Greyhound bus. On December 24th we embarked on Whitsunday Magic, a 113ft three-masted Schooner, for a three-day cruise around the Whitsunday Islands. We had an awesome Christmas Day on Whitehaven Beach followed by a not-less-awesome Christmas lunch onboard. The weather was good, but as you can see on the picture above, clouds were starting to come in.

Boxing Day was really bad, with continuous rain, big waves, and the ship oscillating in pitch pretty badly (I’m sure sea people have a proper name for that). We managed to go snorkelling in the rain in the morning, and I went diving in the afternoon at Cave Coves near Cook Island. As expected, the visibility underwater was bad with low light, but I was happy I could spot a few species of fan coral not found in the (relatively) colder waters near Brisbane. We also saw a few beautiful nudibranchs and flatworms. One good thing was the water temperature at 28 degrees.

On Thursday the rain didn’t stop for the whole day. As my girlfriend’s father would say, Heute regnet es nur einmal, i.e. it only rained once today. We were back onshore in Airlie Beach around lunchtime and later hopped on the Greyhound back to Mackay. The driver chose to screen the movie The Rundown. For some weird reason, the title of the movie was changed in Australia and the UK to Welcome to the Jungle. Suffice to say the only redeeming feature of the movie is a fantastic flying scene over moutains in the Amazonian Jungle in a small high-wing taildragger.

Now, the initial plan was to take a short 10-minute flight on Friday morning from Mackay to Keswick Island and spend two nights at Keswick Island Guest House. When we showed up at Australasian Jet in Mackay we were told that all flights to Keswick Island had been grounded for the last two days, and that today was probably not going to be any different. We still waited a couple of hours in the hope that winds would fall but by about 10AM we had to give up. We decided to shorten our holidays and get back to Brisbane. The pressure chart for that day shows a strong low over the Coral Sea. This low is the east-most point of a monsoon trough whose west-most end is another low off the coast of North-Western Australia that would become tropical cyclone Melanie over the next days.

We could have taken a Jetstar flight leaving in the next hour but $500 per person for a one-way flight is more than I am ready to pay for air travel, however convenient. So we decided instead to take a later Qantas flight for less than half the price. But the bargain came with strings attached. Flight QF2307 is actually flown by a Dash-8 and could be called the Queensland Flying Omnibus. It leaves Cairns at 12:40PM and stops in Townsville, Mackay, Rockhampton and Gladstone before reaching Brisbane at 6:05PM. Needless to say, my better half was a lot less excited than I was at the prospect of spending the next three hours in a turboprop with a fair chance of turbulence and two more landings and take-offs than necessary.

The flight was one hour late in Mackay and we had to perform the infamous “dash for the dash” under the rain to board the plane. The runway was wet as we took off. The flight to Rocky turned out to be very smooth, cruising at 17,000 ft between two layers of clouds. I had a window set with a great view of the right engine and landing gear, which would have turned into a rather spectacular and dangerous vantage point if the right landing gear had collapsed like in this recent SAS flight. A very good write-up was written by Sam of Blogging at FL250, who is himself a former Dash-8 pilot.

We refuelled in Rocky and then took off again for the 25-minute leg to Gladstone, and after that it was off to Brisbane. We arrived from the north-west, flew abeam Redcliffe on our left, then followed the shore of Bramble Bay and finally landed on Runway 14.

Since we came back last Friday I’ve been keeping an eye on the weather forecast. And it does not look good for flying tomorrow Wednesday and on Friday. The low over the Coral Sea that shortened our holidays is still there and produces rain and strong south-easterly winds in Redcliffe. Remember, winds blow clockwise around a low pressure area in the Southern Hemisphere.

Today the weather observation in Redcliffe gives SSE winds of 25-30 knots gusting at 35. Given that the runway orientation is 07-25, this means almost a direct crosswind. The maximum crosswind component for the 152 is 15 knots, to say nothing of my own ability to deal with crosswinds, so that in itself means no flying tomorrow.

If that was not enough, the forecast for Area 40 reads:


and the visibility in showers is forecasted at 3000m and 4000m in drizzle. That’s not even VMC which requires at least 5000m visibility below 10000ft.

So that’s probably a no-go for tomorrow. My hope for Friday is that, with the wind as forecasted at 20 knots from the east, the crosswind component will be acceptable. On the other hand, heavy rain is forecasted too, which means we may have to part with VMC.

Fingers crossed that I can fly at least once this week, otherwise I will have time to perform an upgrade on my home PC (the first one in four years) to bring it to an acceptable level to run X-Plane. More on flightsims in future posts hopefully.