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The legendary “three holer” − Boeing’s 727

The Boeing 727 was one of the most beautiful looking airliners ever built. Of all the early jet airliners, the 727 had the most distinctive appearance.

Whether parked on the flight line or in flight, its sleek lines, rakish T-shaped tail and its trio of rear-mounted engines would simply take one’s breath away.

A sophisticated design

The 727 was designed and built in a bygone era, shortly after the advent of the jet age. This was in response to a particular demand for jet liners that could operate short to medium-distance flights from small airports.

The aircraft was equipped with an auxiliary power unit (APU) which provided both electricity and compressed air for air conditioning and engine starting. Ground power units were no longer required.

The elevators, ailerons and rudders were all hydraulically powered. There were two sets of triple-slotted fowler flaps on each side. Collectively they could increase the aircraft’s wing area by a huge 25 %. The aircraft was also equipped with a nose-gear braking system which enhanced braking capability. There was no real need for a passenger stairway as a retractable staircase at the back of the aircraft, below the middle engine, allowed for entry to and exit from the aircraft.

In short, the aircraft fulfilled all the objectives that had been defined in order to allow operations from the smaller airports with short runways.

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Special flying techniques were required

We were trained to avoid unstable approaches at all costs. This was as a result of four horrific accidents that occurred within a year of the 727s  entering service in 1965.

The cause of all these accidents was that on the approach to landing, the aircraft were descending with high flap settings and low thrust. There was no real appreciation from the pilots as to the huge amount of aerodynamic drag that these flaps produced.  Entering the approach environment, when the rate of descent needed to be arrested, the “spool up”” of the engines would be too slow for the approach to become stabilised. The aircraft then continued descending until they crashed.

To eliminate any further such accidents, massive emphasis was placed on no more than the initial approach flap setting being selected until the engines had been spooled up. Only then could the landing gear and full flaps be extended.

Pilots all over the world were taught to fly the aircraft in this manner and there were no more of these accidents.

The 727 was a great performer

Of all the many airliners I’ve flown, the Boeing 727 is my favourite. The aircraft’s technical systems were managed by the flight engineer. The pilots could therefore give their full attention to the flying.

With the engines mounted at the rear, they were barely audible in the cockpit. On take-off, all you heard was the sound of the nosewheel on the runway and then a gradual increase in wind noise as the aircraft accelerated.

The standard cruise speed as laid down by the company was Mach .82. If time had to be made up because of a delay, the speed could be pushed to as high as Mach.86.

When approaching our destinations, the standard descent speed was 280 knots IAS. However, once we had transitioned from Mach number to indicated airspeed, usually at about 24 000 feet, we could speed up to an IAS of 410 knots. Thereafter, descending to sea level,  the speed would be reduced gradually to 380 knots.  For an airliner, that was really very fast!

The speed-brake was hugely effective. When it was deployed you could physically feel the deceleration, and within a few seconds or a very short distance, you would have gotten rid of all the excess speed and would be at a speed low enough to run the flaps.

Approach and landing

With its triple-slotted fowler flaps and the huge amount of lift and drag that they created, the aircraft was incredibly speed-stable on the final approach. Once established on the glideslope and fully configured for the landing, you set the thrust at about 78% N1, which is actually quite considerable. Thereafter, you seldom if ever needed to alter the thrust setting unless severe updrafts, downdrafts or windshear was encountered.

The 727 was fairly difficult to land in that the main wheels were a long way back from where the cockpit was. It was best to try and fly the aircraft down as close to the ground as possible and then push forward on the control column so that you “rolled” the aircraft onto the surface. If you left the flare for too late and then snatched back on the stick, you would drive the wheels into the tar.

The virtues the Boeing 727 − its systems, handling qualities and performance − led to it become an all-time favourite among those who flew them.




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