Ilyushin Il-62

A version designated Il-62MK was designed as a much modified medium-range machine, though it never reached high production and was dropped from the programme by 1978 (although Germany operated two examples).

Other versions were also planned, some "stretched" to seat up to 250 passengers and others suited to small airfields. None of those reached the detail design stage.

No civil/military or military developments are known.

MK

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The Il-62 has a conventional landing gear with an additional trademark lightweight landing gear strut at the rear of the fuselage which extends when the aircraft reaches its parking position.

Aircraft with rear-mounted engines are usually tail-heavy when sitting empty on the ground, and to prevent the aircraft from tipping up on its tail, various devices are used for supporting the tail - from simple "pogo stick" fixed struts on small aircraft, to light-weight extendable struts (Il-62).

Aircraft like [Vous devez être inscrit et connecté pour voir ce lien], [Vous devez être inscrit et connecté pour voir ce lien]/[Vous devez être inscrit et connecté pour voir ce lien] or [Vous devez être inscrit et connecté pour voir ce lien] use an airstair door under their tail which serves the dual purpose of a tail support as well as an extra door for passenger loading.

The Il-62 is the largest airliner with [Vous devez être inscrit et connecté pour voir ce lien], using steel cables and rods, pulleys, aerodynamic and weight balances, and trim tabs.

There are also indications that the Il-62 has a forward-mounted tank for water ballast.

This may be used when the aircraft flies empty or lightly loaded.

If this is a fact, it would rank the Il-62 alongside other airliners that use ballast, notably the French [Vous devez être inscrit et connecté pour voir ce lien] and the Soviet [Vous devez être inscrit et connecté pour voir ce lien].

Due to the rear mounted powerplants, the wings are aerodynamically clean, and takeoff and landing aids are employed without the disturbing effect of engine nacelles, resulting in free airflow over the dorsal wing surface.

Thus the aircraft can fly through [Vous devez être inscrit et connecté pour voir ce lien] of 16–18 m/sec without affecting its stability (Thiel, 2001).

Another key Il-62 trademark is the "saw tooth" ("dog tooth") on the wing leading edge.

This prominent feature acts as an aerodynamic fence [Vous devez être inscrit et connecté pour voir ce lien] (without which the wings would be almost vortex-free), and fixed leading edge droop/slat/flap.

It ensures vice-free behaviour at high angles of attack and assists efficient long-range cruise.

The saw tooth removes the need for hydraulic controls, stick shakers, and stick pushers.

Interestingly, later models of the [Vous devez être inscrit et connecté pour voir ce lien] (for [Vous devez être inscrit et connecté pour voir ce lien] and [Vous devez être inscrit et connecté pour voir ce lien]) also adopted this feature, in their case closer to the wing tips.

Early N-K 8-4 engined Il-62's suffered from indifferent performance as well as engine [Vous devez être inscrit et connecté pour voir ce lien]/overheating, sometimes leading to false fire alarms whereby the crew might be tempted to shut down paired engines to prevent contagious engine and fuselage damage.

Flying with only two paired engines on the same side would, however, render the aircraft unbalanced and difficult to control.

Subsequent modifications to the Il-62 and the VC10 (which had a similar engine arrangement) largely rectified this problem.

There were two fatal Il-62 losses involving engine failure, both occurring with aircraft owned by the Polish airline [Vous devez être inscrit et connecté pour voir ce lien] which had also leased a number of Il-62s from Aeroflot and [Vous devez être inscrit et connecté pour voir ce lien].

The higher fatality accident (183) was a fully-laden Il-62M [Vous devez être inscrit et connecté pour voir ce lien] on 9 May 1987 which experienced a rear fuselage fire that possibly went unnoticed by the crew, hence their decision not to land at one of two nearby airports.

Control of the plane was eventually lost on the return flight to Warsaw.

The other was an unmodified (early version) N-K 8-4 powered Il-62 [Vous devez être inscrit et connecté pour voir ce lien] which crashed on 14 March 1980 with 87 fatalities after being fitted with an engine that had previously caused vibration problems when used on two other LOT aircraft (the investigation suggested that the turbine disc was damaged before its final installation on SP-LAA).

Powerplant failure of the type that afflicted the LOT aircraft was extremely rare because bearing wear is generally identified by vibration tests during maintenance.

At the time, however, LOT did not have equipment to test or fault-diagnose engines of the size used in the Il-62.

Unfortunately this meant that any potential problem might not be identified between overhauls.

There were other known instances of engine failure (eg YR-IRD & CU-T1283) but these did not result in loss of control.

The LOT accidents involving different engine types (but same engine position) was a fatal crash-rate 30 times higher than the Il-62 average (2.8% vs 0.092%).

At least one other LOT [Vous devez être inscrit et connecté pour voir ce lien]-equipped aircraft ([Vous devez être inscrit et connecté pour voir ce lien]) also suffered a similar engine failure (non-fatal) around this time.

After 1987, LOT introduced turbine vibration-detecting equipment and shortened the time between inspections.

It also adopted the dual flight control system used on some other Il-62s and deleted the auxiliary engine-pod fuel tanks.

These planes were subsequently onsold to [Vous devez être inscrit et connecté pour voir ce lien] in 1991/1992 which operated them until 2000.

In 2010, 30 years after the loss of Flight 007, an investigation of previously unreleased [Vous devez être inscrit et connecté pour voir ce lien] archives at Instytut Pamięci Narodowej revealed that during the industrial unrest of the 1980s LOT had been instructed by the [Vous devez être inscrit et connecté pour voir ce lien] authorities to effect operational cost savings by over-exploitation of service life of its jet engines ([Vous devez être inscrit et connecté pour voir ce lien] Causes of disaster).

Special Il-62 conversions

Several special conversions were made to the basic Il-62, the main ones being the Il-62 and Il-62M salon VIP versions used by heads of state, and the Il-62M airborne command aircraft (just one example) used by the Russian government (Gordon et al., 2004).

Although the Il-62 had been introduced during Khrushchev's time, it was during the Brezhnev era that Ilyushin was asked to develop the salon versions which have been used by Russian leaders ever since right up to the Putin years (during which time both Il-62 and [Vous devez être inscrit et connecté pour voir ce lien] aircraft were used in combination).

The VIP examples were fitted with conference rooms and rest areas, rooms for the retinue, and service personnel and bodyguards, while the secure communication equipment enabled contact with Moscow and other cities from any part of the globe.

Examples were also delivered to other countries including Czechoslovakia, Germany, North Korea, Sudan and Ukraine.