Having learnt about VORs last week it was time to begin focussing on flight by GPS, a form of "Global Navigation Satellite System" in aviation speak or GNSS for short. As GPS is such commonplace these days I'll bet you've even a device near your person that can make use of it! As a result it should perhaps come as no surprise that aviation employs it extensively in various phases of flight. Further to this, various aviation authorities around the globe have started discussing how it could be rolled out to replace the more traditional ground-based navigation aids although the implementation of this is still a decade or two away at least!
What exactly is GPS?
Initially created as a proprietary aid for the United States Military, the Global Positioning System (GPS for short) employs 24 orbiting satellites (as per graphic) to provide accurate position, tracking and altitude data to the majority of the Earth's surface. The highest levels of accuracy remained locked from public use until the early 2000's where it has since developed to the service we use today. For accurate position fixing a receiver requires a line-of-sight connection with four satellites although will often connect to many more than this. Where greater than four are available, automatic integrity checking exists to ensure the data displayed comes from the most accurate satellites. On the whole, GPS is said to produce accurate fixing to within 5 metres - that's pretty damn accurate!
How is it employed in Aviation?
As modern day aviators we're able to make use of GPS in various phases of flight as either a complement to more traditional systems or a direct replacement. Examples of how you might use GPS include:
What did we cover in the lesson?
The lesson began as normal and I started the sim up from cold and dark but the biggest difference and first main teaching point was configuring the flight computer. Sadly, flying with GPS is not as easy as tuning up a navigation aid on your radio stack and spinning your bug to a set heading.. there are numerous steps. Equally, who'd have thought there'd be so many variations to an approach for one given runway!! The first thing we did was discuss which approach and arrival we'd like to make into Hamilton and briefed the appropriate plate(s). We then moved on to entering all of this into the Garmin G1000 where I learnt that despite how clever it is, the interface is mighty clunky at best! We got there in the end though and everything was setup correctly. Taking off I tracked the VOR standard instrument departure (SID) before then telling the G1000 I wanted to fly with the route entered earlier. A few button presses later and a magical magenta line had appeared highlighting exactly where the route would take me. I could zoom in and out of this and move around it as my heart so desired but that wasn't the objective here which of course, was to fly the arrival and approach back into Hamilton.
One thing I liked about flying with a GPS route programmed in this way is that it tells you exactly when to turn and onto which heading. For example, when almost at the end of the arrival and getting ready for the approach / descent it would display "Turn 176° in 3..2..1..." and then would adjust the bugs on your compass rose automatically. My brain was needed in order to account for wind but once you get used to the GPS way of doing things it's certainly a positive change. The drawbacks with flying this style of approach is everything happens a heck of a lot closer to the airfield. For the "RNAV Zulu" approach I rolled out onto final roughly 4 - 5 miles from the runway whereas on the VOR/DME approaches you're around 10 miles away. This was a clear demonstration as to why pilots need to be at least one to two steps ahead of the aircraft at all times - particularly prevalent if you were to employ autopilot at this moment.
What about en-route GPS stuff?
We're only being taught instrument navigation aids in regards to the departure, arrival and approach into airfields currently. Once we've had time to get our head around that and also fly it in the actual aircraft then we'll be back to the sims again to start looking at some more en-route topics. This will no doubt crop up in another blog post down the road.
It was another bright and early start today, with a simulator report time of 05:55. Thankfully my instructor and I were zombie like and with no bookings directly after us he pushed it back a tiny bit to allow for a fix of caffeine. Hopping into the sim around 06:15 I started everything up as usual before being given the brief for the flight. This sim flight, like the first solo check a few months back, represents a critical point in training whereby the school is able to ascertain whether a trainee would be safe to go and fly a real aircraft using the VOR and GPS navigation aids. To ascertain this my instructor had me fly different entries into a holding pattern, two VOR/DME approaches, two missed approaches and finally a direct tracking to the GPS arrival, with one hold and one GPS approach down to the runway. The session lasted about an hour and a half and I'm pleased to say I passed it!!
The next time I fly with instruments will be in the Cessna sometime this week or next. Between now and then though I believe there's another set of mass briefs we need to complete in addition to the Multi-Engine Class Rating exam paper so it seems as though its very much head back in book for a little while.
With Sunday marking the completion of the first six IFR sims I was told I was slightly ahead of our timeline and would have Monday & Tuesday off to allow the rest of the group to catch up. It's odd to be one of the frontrunners when not too long ago I was almost 20 lessons behind, but a lot of that has to do with availability of instructors / trainees / aircraft / sims and thus occurred through chance more than anything. If one thing's for sure though it's that having two days off on my own was boring and there's only so much scrolling through Facebook / Instragram / watching Netflix you can get away with before even that gets dull - I name that the Clearways effect. Sharing cars may be great in terms of cost but when you're on a day off by yourself you feel a little trapped. I had good ol' Wilson keeping me company though.. I love that film!
Towards the tail end of Monday our group received an email to inform us we'd be sitting an exam paper for our EASA Multi-Engine Class Ratings towards the end of this week. Eeek... so with nothing better to do I spent some of Monday / Tuesday reading through the 100 odd page multi-engine training manual provided to us during the start of the Twinstar training. For readers unsure of what a Class Rating is, I suppose you could consider it similar to categories on your driving licence. When we qualify from L3 Airline Academy we will posses a Commercial Pilots Licence with a Multi-Engine Class Rating attached. This means that I and my coursemates will be licenced to carry out the privileges of the CPL on any multi-engine aircraft below a certain mass. In other words, I can pop down to the local flying club and hire a multi-engine propeller aircraft and go for spin. To obtain a Class Rating a trainee must complete a set number of hours in a multi-engine aircraft, which we've already attained during our VFR Twinstar flying, in addition to a passing an exam paper related to aircraft of the same type. In the case of L3 Airline Academy the paper is split to focus some questions on general multi-engine aircraft and the remainder on the DA42 we're accustomed to. Sadly, integrated training courses do not permit you to fly single engine propeller aircraft post graduation and the associated class rating for that would come at the trainees own cost. In the interest of a hobby and being able to share the joys of flight with family, that will almost certainly be something I look to achieve at some point post-graduation.
On Wednesday my course were booked in for the second block of mass briefs linked to IFR flight. The typical EASA course structure at L3 Airline Academy, New Zealand, sees a cadets fly the Diamond DA20 prior to transitioning to the Cessna for the first few IFR flights and then onwards to the DA42. Therefore, the majority of today's briefs were related to the specifics of the Cessna 172 and, having already flown it, two coursemates and I asked if the instructor would cover the non-Cessna briefs first - to which he agreed. During the briefings we were taught how, when and why we file IFR flight plans with New Zealand's Air Traffic Control authority, Airways, before discussing calculating wind direction and what factors come into play when considering alternative destinations. Having learnt that the existing Cessna group then left for the day. To kill some time I popped into town with my coursemate Ian to grab a few bits and bobs from the stationers before tucking into a caramel slice and flat white at a coffee shop on the way home. Yum. The weather for the remainder of the day was pretty awful so the vast majority was once again spent bored out of my mind and/or reading the multi-engine book. I did manage a trip to the gym though, so that's one plus point.
Okay.. i think we have an addiction to coffee. The amount of trips we've made to coffee shops to cure boredom is beyond belief! I've now a narrow list of favourite places to go though so if flying doesn't work out maybe I should turn to food / drink critic instead. All joking aside though, today was just like any other day. Wake up, soon settle into boredom and go on a trip out to kill time. After a quick wander around the supermarket and the above caffeine fix I returned to Clearways to get ready for my flight: The first IFR flight in the aircraft.
I'm was looking forward to going flying again as it's been over a week since my cross-country and the simulators are not anywhere near as close to the real deal! The first few IFR flights essentially replicate what we've done in the simulator and as such flight one is a VOR Holds / Approaches lesson about 6-7,000ft above the airfield. Can you guess what came next though? Yep... poor weather and despite a lush winters morning with temperatures around 16°, the sky was very active in producing several towering cumulus clouds. A couple of my coursemates managed to get up in the morning and the first was able to complete his lesson. Sadly the second had to come back early due to the accretion of frost / ice on the wings. In your modern airliner ice isn't so much an issue as incredibly hot air from engine combustion chambers can be fed to the surface of the wings. While this keeps passengers flying on their holidays that technology is rather expensive and as such not practical on your little ol' Cessna. The Twinstar, however, is better equipped in this sense and has anti-ice fluid to extend safe flight time in icing conditions. We'll be going back to the Twinstar in the not too distant future.
* Towering clouds as seen from the cockpit of a B737 over mainland Europe *
Turning up to the airport a little earlier to read over the requirement to log flight plans etc my instructor came over and pretty much cancelled straight away. He'd not long got back from a flight himself and while they had no issues in the morning, coming back was a different story, he said. Apparently it was some of the worst turbulence my instructor had experienced in some time. I suppose that just goes to show you that while a cloud looks innocent and candyfloss like from the ground, it's far from your best mate up in the air. The student he flew with said a few hail droplets came in through the cabin ventilation as they got closer - you really daren't go near these things!! The photo above was taken from an airline pilots perspective of these clouds and on that day they were forecast between 4,000ft and 36,000ft which just goes to show their vertical extent - nasty things. I've been close enough to one of these clouds before at relatively low level and you certainly feel their might - especially in their early stages of development. So, back to Clearways I went.
Later that day a few of our group suggested we popped to a beer garden at the "Good George Pub" in Cambridge. Great name that, eh! We took our iPads / Laptops and studied for the multi-engine class rating exam booked for this Friday. Safe to say i'm bricking that as it's come around quite quickly! Some of it i'm still a bit rusty on and it looks as though I need to remind myself of aircraft general knowledge. Here's hoping we do well.
Great, the fog is back. There's no towering clouds this time, just dense fog which made the drive into the centre interesting given I could barely see in front of the bonnet! I happened to pull up at the same time as my instructor who told me it wasn't even worth pre-flighting until we could see the fog lifting so I sat watching the outdoors for around 45 minutes. With it looking less and less likely to go ahead and with no schedule movement thanks to the Cessna's being rammed, we cancelled. In the time we had spare I sat and talked through the submission of flight plans and what to enter where etc, which was helpful in advance of future lessons. I then returned to Clearways for some breakfast no later than 50 minutes after leaving.
Once the rest of course started to rise from their slumber it didn't take them long to want to get out again and as such we found yet another coffee establishment to revise in. It was nice to spend a few hours chatting there as well as revising as we typically just drink and then leave. It's good to be able to bounce each other's thought process off one another as we prepared for our 40 question paper later that day - which in itself came and went rather quickly. Thankfully the questions weren't anywhere near as difficult as I was expecting them to be. The Twinstar manual L3 provided and the manufacturers own aircraft flight manual helped us answer the majority of questions and I'm very happy to say I scored 92.5%. So, while I may not have a licence just yet, this pass at least proves I've enough knowledge to attach a multi-engine rating to it on issue early next year. Whoop!
That's it for this week. Not much happened as far as flying goes, but i've certainly a busy weekend what with 3 bookings. Unfortunately it looks as though national air traffic control services are running at lower capacity and such a few of our flights may well be cancelled. If it's not one thing it's another, fingers crossed both the weather and ATC play ball though!
Until next time,