Latest ArticlesAll Articles
I can almost see the initial reader reaction. What is this guy up to explaining such basic manoeuvres to experienced instrument pilots? Most weeks, I fly with pilots whom I have not met before revalidating, renewing or training for ratings. My impression is that few pilots really take positive control of the transition between earth and sky. The majority simply enter into a slightly hesitant negotiation with the aircraft in the hope that it will agree to deal with the transition on their behalf.
Typically, the departure will be a series of increasingly uncomfortable bounces trending towards the runway edge until the aircraft simply feels that flight is now its only option. Arrivals are often about selecting a power setting and some vaguely appropriate pitch angle and waiting till the runway contacts the wheels. If luck is with us, the mains will arrive nano seconds before the nose wheel at a point on the runway of the aircraft’s own choosing.
Typically, instructors say “Adopt the take-off and landing techniques described in the flight manual”. My view is maybe. The typical manual was written by the manufacturers’ marketing department in the late 1960s or early 1970s. In a hangover from the days of biplane trained pilots, the use of flap for take-off tended to equate with a “hot ship”. This had negative connotations and was thought bad for sales. Hence the manufacturers were reluctant to specify flaps for takeoff.
Why would you want those tiny tyres to be in contact with the tarmac for a moment longer than necessary? Always use take off flap - at least one stage and in some aircraft two stages. Always use the short field or soft field rotation speed; they are anyway almost identical. I have never understood the marginal difference in technique that in the past at least was beloved of FAA examiners.
If you fly an MEP, you enter in to the world of balanced field length and minimum control speed. These can result in heroic efforts to keep aircraft that want to fly on the ground with sometimes loss of control as the end result. My suggestion is always use flap, power against the brakes according to circumstances and a positive rotation at the lowest speed the aircraft is willing to fly. The stall warner may bleat briefly; once off the tarmac or grass, push forward firmly and fly level in ground effect. In a few seconds you will be through minimum control speed in a twin and at best climb speed in a single or a twin.
The next near useless distraction is calling “positive rate of climb - gear up” or “no runway remaining - gear up”. In general, a GA aircraft rotating as I suggest will always be climbing. Doubtless there are commercial aircraft or aircraft operated at MAUW where some sink is a possibility but this does not apply to GA aircraft.
(Note there are a very few aircraft, like the BE36 Bonanza, where it is more complicated. The drag of gear retraction is enormous due to the gear door arrangement. The clue is the big difference in gear down and clean best climb speeds; for such aircraft, get some conversion training from a knowledgeable instructor.)
If you are IFR and expect to enter low cloud, the focus should be on getting the aircraft established in the climb with all actions completed before entering cloud and going onto instruments. If, with a very low cloud base, this is simply not possible, you need to establish your scan and not allow this to be disrupted by after take-off actions. In these circumstances you may need to delay any retraction until your scan and climb is well established. That said, if you decide to fly in circumstances that involve short runways and a low cloud base you may be asking for trouble.
So the take-off is full power, into wind aileron to counter any cross wind, a quick glance at the instruments to see nothing is amiss with the engine, ease the weight off the nose wheel and at the lowest reasonable rotate speed, give the yoke a positive pull back then, almost immediately, ease forward. A slightly aggressive version of this technique will make even an aircraft with a poor take off performance like a T tail arrow into a reasonable short field performer.
Almost immediately raise the gear and flaps (in stages if necessary). The couple of seconds delay between gear and flap is to spread any peak electrical loads which may pop a breaker. In most aircraft you will now easily be at best rate of climb speed and a 6 or 7º pitch up will give you a decent performance. By now you will be six or seven hundred feet above the runway and can quickly run your after take-off checks, knock off the fuel pump if used and concentrate on navigating your first leg and making a reduction to climb power if required.
If I had been writing this article a month earlier, I would have said that mechanical fuel pumps were totally reliable and putting on the electric pump was a waste of time. Now I am not so sure; a few weeks ago passing 1000 feet, the rate of climb sagged and as I looked for the cause the TIT alarmed and the engine started to wind down. It appeared the mechanical pump had failed. Selecting low boost had no effect but the guarded switch for high boost did the trick. Even here, simply selecting low boost for take-off would not have helped and in normal circumstances, high boost with a working mechanical pump, will also stop the engine. It is Hobson’s choice.
When it comes to landing, very few pilots seem to select an aiming point on the runway and then direct the aircraft to that point by use of the controls. You point the aircraft where you want it to go and then, by changes of power and perhaps configuration, make it go where it was pointed at the target speed.
In most circumstances the desired configuration is, unsurprisingly, gear down and full flap. In spite of the well documented tendency for even experienced pilots to land gear up, very few pilots bother with a final approach check. At Rate One Aviation, we use “LUC” rather than “reds blues greens” or “PUFA”. We think it is a bit late to be worrying about altimeters at this stage in the approach and we have found that without a reminder pilots forget about the need for a clearance. Thus L for levers means whenever you make a significant change of any control lever, usually the throttle, you consider all three, U for undercarriage of course and C for clearance for a landing or low approach. We run this check twice, one just before the final descent and again when visual.
The transition from instrument approach speed to full flap limiting speed is sometimes a problem. There is never any justification for changing the aircraft configuration while on the ILS. You select whatever is appropriate, the top of the drop most often for gear and one stage of flap, prop full fine and mixture rich. Then do not change anything that might destabilise this critical phase of flight until you become visual.
Off an ILS to minima, you may be better off landing with part flap, but on a non-precision approach there is plenty of time to bleed off a little speed and select full flap if the flap limiting speed is an issue. I have to admit to being a little casual in the past about the low flap limiting speed on our aircraft, but very expensive repairs to cracks in various bits of flap related structures have now persuaded me otherwise.
Most heavier aircraft like to carry a trickle of power into the flare. In any sort of cross wind you will have to kick off drift and lower a wing so that the into wind main wheel touches first. It should be possible to keep the column coming back almost to the extent of its travel as the speed decays. The nose drops naturally to the ground having bled off a significant amount of speed. This helps avoid heavy braking that risks flat spotting the tyres.
Most GA types at reasonably light weights should be able to be down and stopped in 500 meters if handled properly. Why not take a safety pilot and do some practice? It is good fun and one day may save you a lot of money. I once flew a session with an experienced pilot who had come for instrument practice. His instrument flying was good but his landings left me quite worried that I was about to become intimate with the upwind boundary fence on a 1400 metre runway. I said nothing as he had just revalidated a mountain rating at a very demanding tiny airstrip so I persuaded myself he was just having an off day. The very next morning he ran his £300K aircraft through the upwind fence of a small airfield in some style. This was a lesson for me as an instructor to always say what you feel needs saying. It also emphasises the point that it is not uncommon for pilots to be quite good at instrument flying while at the same time having allowed their basic airmanship to seriously decline.
- Category: Using the Rating
- Created on Friday, 30 December 2016 08:38
- Last Updated on Friday, 30 December 2016 08:41
- Published on Friday, 30 December 2016 08:38
- Jim Thorpe
- Hits: 1731