For the first time this winter I felt like I was in a winter wonderland with full use of Winter operations. As we descended down over Eastern Europe, I could see that the ground was covered in snow – as far as the eye could see. With the temperature being -11C, and snow everywhere, it reminded me that we would have to adjust our operations to the weather.
We started by adjusting the Minimum Safe Altitudes (MSAs) and any altitudes below this, to compensate for temperatures below 0°C. This is because any temperature that differs from 15°C, which the instruments are calibrated to, introduces an error in the altimeter. Warmer temperatures will make the altimeter under-read, whilst cooler temperatures will make the altimeter over-read. This is because when the air temperature changes, the air expands or contracts. If the air is cold, it contracts and so the pressure levels bunch up closer together. The opposite happens when the air is warm. The altimeter works by being sensitive to the air pressure – consequently it causes errors in the reading when air temperature diverges from the calibrated temperature of 15°C. We don’t make any temperature corrections for warmer temperatures because an under-read does not affect safety (the aeroplane is actually higher than what the altimeter is indicating) and everyone else’s altimeters would be reading the same in any case and there wouldn’t be any issues with traffic separation.
We found the runway was cleared from snow, giving us plenty of room to land safely. Once we landed we ensured we taxied slowly and cautiously, as to not skid or slip, and followed our winter procedures. It did add to the workload, so everything had to be done without rush as usual and meticulously. During the turnaround we checked the wings to ensure they were clear of ice. This reminded me of an Air Crash Investigation episode I was watching a few days ago – where a Boeing 737 crashed into the Potomac river in Washington, shortly after takeoff. The aircraft crashed because the the wings were not de-iced and consequently the ice changed the aerodynamic characteristics of the wings, leading to an early stall. The episode gave a bit more detail and there were other factors involved, however it shows how import it is to remove ice off the wings and take off with a clean wing.
When we de-ice we usually apply fluid to the wings which removes any existing ice and protects them from accumulating any more ice for a certain period of time. This period of time is often referred to as the “holdover time”, which is dependent on the concentration and type of the fluid sprayed onto the wing. So, next time you are in cold and icy weather and you see some fluid being sprayed onto the aircraft from a large hose, then you know your aircraft is being deiced!
Thankfully it’s not snowed much in Western Europe this Winter, so we’ve not been afflicted by the consequential delays that come with winter operations. We still have a couple of months to go though, and it can still snow in April! I was looking at the news and saw the weather in North America – let’s just say that I’m glad we aren’t experiencing the same here!
“Train the crew to make safety their highest priority when making decisions.”
I was just watching an episode of Mayday/Air Crash Investigation, and it made this important point. Though there has always been emphasis on this on every simulator training session I have had, the last training session in the simulator particularly focussed on this. The training sessions usually have three main elements – a briefing, the simulator session and a debriefing. The briefing mainly consists of reviewing the items that we will be practicing in the simulator, looking at & discussing case studies and crew resource management training. We then go into the simulator for about 4 – 5 hours, and get the opportunity to practice emergency and non-normal scenarios and we are also tested on them. The session can be tiring but it really does go very quickly despite the amount of time spent in there. Once the simulator session is over, we go over what went well, what we can improve on and what we have learnt.
The aim is always to feel like you’re a better pilot having practiced manoeuvres that cannot be on the line (unless there is an actual emergency), and ideally come out with more confidence in your own skills. However, this is not always the case – anyone can have a bad day in the simulator where they’ve not performed their best, leaving them feeling disappointed with themselves and as a result, less confident. How do you deal with that? You take notes and learn from your mistakes and use it as a learning experience to motivate you to do better next time. If I have the odd day where I’ve not performed well, I do look at what I haven’t done well and learn from it, however I also look at my performance over a period of time rather than a single snapshot to give me a better indication on how I am doing. We are humans and I don’t think it’s fair to judge someone based on one test, but rather look at a range of tests over a period of time and see what the trend is!
We have simulator checks every 6 months, so there’s always a chance to improve on the last check and there’s always something new to learn!
I’ve had a busy couple of weeks with line checks and simulator checks, so though I had some time to enjoy the festivities, I had to be disciplined and set aside time for study – and it paid off! The simulator checks consisted of the usual training – practicing engine failures, circling approaches, and dealing with various system failures. In addition to this, the new item on the syllabus was an RNAV approach – this type of approach is where the aircraft navigates using the GPS system without reference to any ground based navigation aids. Most airports that we fly to currently have ILS or NDB/VOR approaches – all of which use ground based navigation aids. The main point I took away from the training on this type of approach was that the aircraft’s lateral and vertical path must be carefully monitored (as with any other approach of course) which must adhere to a certain degree of accuracy.
Outside of flying, I’ve also been busy with iOS development – serving updates to my loyal app users. Apple shutdown the developer portal where we upload our updates over the holiday period for a week, so it was a bit frustrating to not be able to deploy updates – both for me and app users. However, they were good enough to expedite my update after telling them it was critical!
Back into flying – I’ve been mostly flying towards Eastern Europe, and a few flights South towards Spain. It’s been a mild Winter so far, and we’ve not had to de-ice much, and I’ve not yet seen snow anywhere! I’m not complaining! Other than cold weather and snow, I find Winter also brings gorgeous sunrises/sunsets.
Coming back home, you can get some dramatic views with the clouds allowing some of the sun to filter through, producing some defined rays.