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| Cessna 152 instrument panel |
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| Piper Archer TX instrument panel (from www.piper.com) |
So a little bit of basic info on the Archer TX that I will initially be flying out here. The Archer is a single engine, low wing, 4 seat, tricycle carriage aircraft with a 180bhp engine with a 2-blade fixed pitch propeller that pretty much looks like your typical light aircraft. As stated above what makes this aircraft different to a lot of other light aircraft is the G1000 electronic instruments giving it more of a feel of the instruments you'd see on an airliner. In reality, although this is a 4 seat aircraft it can only carry 3 adults and about 3/4 full fuel tanks before reaching it's maximum take off weight of around 1156kg. Controls are conventional, pulling backwards and forwards on the control column moves the elevators (since it's an all moving tail on this it's technically a stabilator), turning it left and right moves the ailerons and pushing on the rudder pedals moves the rudder. It's a nice aircraft to fly, very stable and about as responsive as you'd want a training aircraft to be on the controls.
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| Piper Archer TX |
The pace of lesson delivery here is really quick, I started flying just over a week ago and have completed 6 lessons and 6.5 hours of flying already. At this stage we've just covered the basics such as the effects of controls, straight & level flight, climbs, descents, turns and finished the week with some steep turns and stall practice. The effects of controls lessons were to teach that making a control input on one control will have secondary effects that need to be countered. For example, making an elevator input will change the pitch of the aircraft which in turn will change the speed. Making an aileron input will roll the aircraft and will also cause an yaw in the opposite direction known as adverse aileron yaw (due to the up-going wing having more lift and hence more drag than the down-going wing, this tends to pull the up-going wing slightly backwards against the direction of the turn) that needs to be corrected with rudder to coordinate the turn.
The straight & level, climbing, descending and turning lessons were all about building a mental picture for each of these flight conditions. At this stage of training we are primarily visual pilots, this means our attention should be mainly focused outside of the aircraft confirming the attitude and looking out for traffic with just the occasional glance (typically 20-30% of the time) at the instruments to confirm the aircraft is at the correct speed and on heading & altitude. The idea is to be able to perform all basic manoeuvres with reference mainly to outside datums that you establish relative to the horizon and just confirm that with the instruments, seems like a waste of those nice shiny G1000 displays at times. All these manoeuvres are then performed with different power, airspeed and flap settings to get used to how the datum changes with these.
Straight and level does exactly what it says on the tin, learning to hold the aircraft straight (on a specific heading) and level (at a specific altitude). Straight is pretty easy to hold, as long as the wings are level to the horizon and the aircraft is balanced then the heading of the aircraft will stay on whatever you rolled it out on. Level can be a bit more tricky to hold as the aircraft usually wants to climb or descend if you don't have exactly the right input on the elevators, to counter the need to hold pressure constantly on the flight controls to keep the elevator in the right position we can trim it. Trimming the elevators involves moving a little tab on the elevator surface with will alleviate the control input required, you trim the aircraft to hold a speed and the aircraft will then hold it. So for example if you want to fly straight and level at 100 knots then you set the throttle for the correct rpm to give 100 knots, hold the aircraft level and last the speed stabilise and then trim out any forces you need to hold on the controls to make things easier and free up your concentration to allow you to perform other tasks.
Climbing and descending are essentially opposites of the same tasks and are required if you want to get up above the ground on take off and get back down to the airfield at the end of a flight. The main things to think about during climbs and descents are holding the correct airspeed, maintaining a good look out, engine management (the engines can get very hot in a climb and very cold in a descent) and correcting any slip to stay coordinated. It might seem a little backwards but pitch is used to control airspeed and power is used to control the rate of climb/descent. This is because all climbs tend to be performed at full throttle and descents are either glide (idle power) or part power depending on what airspeed and rate of descent you require.
Turning is also a required skill unless your destination happens to be exactly lined up with your take off runway. Turns are basically performed by banking the aircraft one way or the other and letting some of the lift from the wings pull the aircraft through the turn. Since some of the lift is now been used to turn the aircraft a slight pitch change is needed to stop the aircraft from losing height, good use of the rudder is needed to coordinate all turns as well. Typically in light aircraft all turns are performed with 30 degrees angle of bank and no height should be lost or gained whilst turning.
I've talked a bit about coordination of manoeuvres above so should probably explain what it is. In it's simplest form coordination is ensuring the tail of the aircraft follows the nose and isn't out to one side or the other in a slip or skid. If the aircraft is in a slip or skid then we're not flying efficiently (as we're now presenting more of the aircraft to the airflow) and in certain circumstances this can significantly increase your chances of spinning. We have a little instrument on the display called a slip skid indicator which will show if the aircraft is not in balance and which way it is out of balance, this is then corrected with rudder. For example, if the indicator is out to the left then more left rudder input is need, sounds simple right? The main problem comes from the fact the any change to the aircraft attitude or controls will change the balance and require a rudder input and if that aircraft is only slightly out of balance this can be really difficult to detect. In turns rudder is needed in the same direction as the turn to counter adverse aileron yaw, when power is increased right rudder is needed to counter engine torque and propeller wash effects (and the opposite with power reduction) during climbs and descents airspeed will change which will require rudder changes. To begin with you're spending a lot of time concentrating on holding the correct attitude, airspeed, altitude, etc. that it can be easy to forget about the rudder and not coordinate everything properly.This aircraft also has an interesting characteristic during take off in that as the nose wheel comes off the ground (and the effect of that keeping us straight is lost) a fairly large amount of right rudder is needed to hold the aircraft on centreline, it's far more rudder than I was ever used to with the Cessna 152.
We also covered steep turns, emergency descents and stalls. These are flight situations you shouldn't ever end up in but are taught so you know how the aircraft handles in these situations and in the case of stalls the symptoms before they occur. Steep turns are basically the same as normal ones but performed at 45 degress angle of bank, at lot more back pressure is needed on the elevator to keep the altitude and extra power is needed to keep the airspeed up but other than that they're pretty much the same. The only time I could ever think this would be needed is evasive manoeuvres in an emergency, or if you'd somehow getting yourself stuck in a valley and needing to turn in the tightest space possible. Emergency descents are basically used if you get an engine fire in flight and need to try to put it out, you basically roll for 30 degrees of bank, bring out all flaps and pitch for 95 knots. This makes you drop like a stone (well over 1000 feet per minute) and gives the best change of putting out a fire.
Stalling an aircraft is not the same as stalling a car, in an aircraft stalling occurs where the angle of attack (the relative angle between the airflow and the wing) is increased until the airflow detaches from the upper surface of the wings and lift is lost. This is obviously not an advisable thing to do and we are shown the symptoms of a stall and how to recover from one so that we hopefully never end up there. The Archer actually has some pretty distinctive stalling characteristics, apart from the mushy feeling controls due to lack of airflow there is also the little computer voice the shouts "Stall, stall, stall" at you repeatedly and a massive amount of airframe buffet. The buffet is caused by the vorticies separating from the wings impacting on the tail vibrating the entire airframe, compared to the C152 which had almost no buffet it really is noticeable. To get out of a stall is easy enough though, just drop the nose a little bit to reduce the angle of attack, let airspeed recover and increase throttle to maximum to climb away. It starts getting interesting if you stall close to the ground where you don't have a lot of room to drop the nose to recover, this is why we practice at least 3,000ft above the ground to ensure more than adequate room to recover, especially if we inadvertently enter a spin (you should be able to recover with a maximum of 100-200ft though).
Basic flying out here can be very challenging at times though, it's getting quite warm in Phoenix now and will only get warmer as we continue into summer. The other day whilst returning to the airfield in the early afternoon it was 38 degrees on the ground (I dread to think how hot it was in the cabin at that point) and I was having to fight huge thermals (in excess of 1,200fpm climb rate) that were trying to throw the plane around whilst keeping the aircraft in a very narrow airspace corridor. It's also a very busy part of the world for general aviation aircraft and you've always got to be on the lookout for potential conflicting traffic, we have a system called TCAS (Traffic Collision and Alerting System) which will warn us about a lot of the traffic but it can be guaranteed to find all of it. There are cool things that happen on almost every flight though, on my last flight whilst returning to the airfield I had a pair of harrier jump jets buzz over the top of my aircraft at about 200ft, the scenery out here is just spectacular (if you like mountains anyway) and since it's free to land at pretty much any airport in America I've already been to more airfields in the last week than I did in the entire of my PPL training a few years back.
What next?
Next week should conclude the lessons on stalling as well as introducing some rudimentary positing holding, instrument flying, practice forced landings without power and engine failures after take off. All being well my first solo should be around the end of the month with the first progress test to follow shortly after that. After that I'll then be flying up to 6 days a week and the pace of training will really pick up.
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