Ellinikon Airport: salvation or white elephant?

By Andrew Leech

Although  the new Venizelos Airport at Spata has been presented to the public as a modern, technological marvel, there are some disquieting questions related to safety that mar this illusion. First, it is subject to windshear and crosswinds, particularly on approach 03 (from the south) where the surrounding terrain magnifies winds and barrels them over the approach path. Ask anyone who has flown into Spata whether they encountered turbulence—there will be more yeas than nays! Even light winds can be magnified to an uncomfortable level while strong ones can be terrifying.

After passing Flebes Island on a compass direction of 03 degrees, the plane lowers altitude and drops undercarriage. Speed slackens and pilots can see the old airport of Ellinikon on the left and the two runways of Venizelos ahead. To the left is Hymittos and on the right is the range near Keratea and another near Saronida. This gives the impression of flying through a giant barn door, with the mountains as doorposts. As they go between these ranges and drop below 2000 ft., the winds start buffeting the aircraft and pilots are constantly on alert to anticipate wind movement and direction.
However, no pilot at Venizelos considers this dangerous unless close to the ground—just uncomfortable. Windshear can, of course, be deadly at the wrong moment and in sufficient strength. If they occur near ground level, windshears (sudden changes in wind direction) can drive an aircraft into the ground. That is what happened to Delta flight 191 in 1985. As the Boeing 737 approached
Dallas Ft. Worth airport, a sudden downburst caused it to crash, killing 133 people.

"By definition, a windshear is a weather event involving abrupt changes in wind speed and/or direction over a short distance. Windshears occurring at ground level are more accurately referred to as downbursts... If the windshear encounter began at a low altitude, such as it would during a takeoff or landing, the overall loss of altitude may cause the aircraft to fly directly into the ground with catastrophic results" (Windshear E. Linacre and B. Geerts 9/'98)

Answers  Athens News  had from a questionnaire submitted to pilots include answers like (1) "I noticed excessive yaw (wing dropping and abrupt pilot corrections), passengers using the sick bag and a general passenger nervousness. And these are big birds." (2) "On two occasions I bet my licence we would do a goaround, but I lost." (3) Another believed: "the main problem is the southerly tailwinds on approach to 03L until around 4DME (Distance Measured Equipment) on the ILS (Instrument Landing System) when you finally "tune" to the local northerly winds. Hence: windshear alerts all the time!" Yet pilots philosophically shrug it off. "We don't build airports," said one, "we just cope with them." "Yes, there is turbulence, but not as bad as Hong Kong," said another. The Civil Aviation Authority's air traffic control chief, Vasilis Eliou, agrees: "We know there is turbulence but it doesn't affect the safety of flights. It has never been reported as dangerous."

The main winds are those coming from the north. However the various mountain ranges distort them, so a wind initially coming from the north may do a U turn and suddenly become a southerly wind. After passing Flebes you encounter a tailwind that lifts the aircraft tail, causing you to lose altitude unless you compensate and increase engine power. It also (being behind you) increases forward speed at a time you want to reduce it for the landing approach.

At 4DME, four nautical miles before reaching the runway, you meet the prevailing northern headwinds in their normal position. However, there is a transition period of being pushed by a southerly and facing a northerly wind simultaneously. This creates turbulence and can produce windshears. The average wind strength in this area is around 20 knots (nearly 40km) so even a large
plane feels it, causing a phenomenon that both lifts and depresses the plane at the same time (causes an up down motion like a lunapark thrill ride) and alters the characteristics of the landing approach path. Fortunately, we usually pass that point before actually landing.

It is to Spata's credit that they installed a specialised wind machine to detect turbulence and warn pilots, but this can do nothing to minimise it or improve passenger comfort, and pilots only receive up to date information just before encountering turbulence.

Another point that came from a senior source at the Civil Aviation Authority, speaking under customary anonymity, was that Venizelos was likely to get severely fog-bound in the winter months and, while this happens to many European airports, Venizelos' equipment was far below the level of that used by a major airport such as Heathrow (they are at Level 3, Spata is on Level 1). He anticipated problems in winter, if hit by particularly bad conditions.

Levels 1,2,3 roughly refer to the generations of equipment and how precise they are. Level 1 on ILS brings you down to 200 ft. above the ground. If you can't see the runway, then you abort the landing and divert to another airport. It also covers 700 ft. visibility ahead of you (RVR: runway visibility range). For a successful landing you need to see both ahead and below. Level 2 brings you down to 100 ft. above the ground with RVR of 1200 ft. while Level 3 brings you down to 50 ft. (in some cases to 7 ft.) and gives RVR of 1800 ft. So far the official recommendation is that Venizelos doesn't need a level higher than 1.

The last disquieting point comes from the fact that if a plane cannot land at Venizelos it must divert to Thessaloniki or Crete: the nearest runways to handle jets of this size. You could theoretically include Mykonos, but if weather conditions were bad in Athens, they are likely to be worse in Mykonos, and transport to the mainland difficult.

The military airports of Tanagra and Eleusis could provide viable alternatives in an emergency, such as fire, engine failure or fuel leak, when passengers' lives are in danger. But they are unlikely to give landing permission to commercial flights under merely windy circumstances. Aside from the security problems of civilians landing at an airbase, there would be the expense of busing them with luggage to Spata's immigration and customs authorities. Furthermore, Tanagra's military ILS system is incompatible with civilian versions.

Since moving to Spata a furor has raged behind closed doors as to what to do with Ellinikon. While the government publicly maintains it would like to build a park, the mayors of the four local municipalities (Glyfada, Alimos, llioupolis and Kalamaki) have privately earmarked the land for housing, with billions of drachmas accruing to those involved.

However, local flying organisations, such as Aeroservices, Aero Leschi Ellinikon, Airman and other private services and clubs have offered a very viable alternative.  Athens News  talked to Dimitrios Daphnis and Petros Sakellariou. Carefully worked out drafts and area plans set aside 20% of available space for Ellinikon's continued use as an airport (small planes and helicopters that make little or negligible noise) leaving a full 80% for future development: either government or private. This plan would also cover maintenance costs of the ONLY nearby runway that could handle an emergency landing of a large jet and relieve the government of some expense.

The question that remains is whether government and local mayors are willing to put a little water in their wine and sacrifice some profit in the interests of safety. With the nearest runways able to handle a diverted flight 600 kms away, Athens may be unique in Europe in being the only capital city with a single major airport and an alternative more than 100 km distant. A certain recipe for disaster if bad weather coupled with severe technical malfunction or fuel shortage/leakage were to occur; if a flight could neither land at Venizelos nor make it to an alternative destination. We faced the same problem with Ellinikon in the past—no nearby alternative runway—but now there is a viable and cheap solution.

An unfortunate Greek character trait focuses only on the present. Let us hope that safety and common sense prevails here and that, instead of merely looking at short-term financial profit, we can look ahead, in time, and ask ourselves the only question that counts: "supposing my child or family were on an endangered flight?" Do we wait for an incident before we lose our complacency and act?


Source:
Greek-American Review, September 2001

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