3.9 The dangers of flight over mountainous terrain and possible decompression

Exercise 3.9.1 Read and translate the text.

The high terrain dictates special planning in case the flight has to divert to an alternative airfield. The concerns are twofold. The first is engine failure, which would force a descent to a lower altitude. Just how much lower depends on the aircraft weight and ambient conditions but the jet’s good performance would keep it comfortably above the safety altitude. The cruising altitude and range on three engines are similar to the performance with all engines operating. The real problem occurs if the jumbo were to lose a second engine and have to descend even lower.

Then more critical consideration is decompression. If the cabin suffers a loss of pressurisation, oxygen masks will deploy automatically, giving the passengers a source of breathable air until the jet can complete an emergency descent. The usual procedure is to descend to 14,000ft, where the air is dense enough that most passengers no longer require emergency oxygen. But in this area of high terrain, descending that low is impossible. Yet the jumbo cannot remain at its cruising altitude – it does not carry enough oxygen to supply the passengers for a prolonged period of time. To cope with these considerations, British Airways developed escape routes to take a jet into areas where the safety height is below 10,000ft. Even then, the airline had to add three more oxygen bottles to each jumbo – 19 in total – to give them adequate oxygen supply to fly these emergency routes.

On the back of the flight progress map is a tactical planning chart that highlights the critical decision points and details the crew procedures to be followed for an engine failure or a decompression.

The decision point for a pressurisation emergency is known as OXY 1. Located 110nm east of Urumqi, this waypoint is inserted in the flight plan and marked on the chart. If the jet suffers a decompression before reaching this point, the flight would turn buck and retrace its route to land either at Urumqi or divert along an escape route north on airway B206 to the Novosibirsk area. After OXY 1, the instructions are to continue to the Yabrai NDB (DY) in north central China and follow airway A596 to Beijing or continue to Hong Kong, depending on fuel. If the jet suffers an engine failure before reaching Yabrai, the drill is to proceed either to Beijing or Hong Kong, depending on fuel. After Yabrai, the flight should continue to the destination.

British Airways uses other imaginary waypoints in its flight plans to denote sections of the route where the safety altitude changes significantly. Past SARIN, for example, ghost waypoint ‘Hotel’ marks the point where the MSA rises from 11,.700ft to 21,100ft.

Exercise 3.9.2 Answer the questions.

1. What does the high terrain dictate?

2. Why are the concerns twofold?

3. What would an engine failure force?

4. What influences a descent to a lower altitude?

5. When does a real problem occur?

6. Why is decompression the more critical consideration?

7. What do oxygen masks give the passengers?

8. What is the usual procedure?

9. Why can’t the jumbo remain at its cruising altitude?

10. What did British Airways develop?

11. How many oxygen bottles does each jumbo have in total?

12. Where is a tactical planning chart?

13. What does a tactical planning chart show?

14. What is the decision point for a pressurization emergency?

15. Where is OXY 1 located?

16. Is OXY 1 inserted in the flight plan and marked on the chart? Why?

17. What would happen if the jet suffers a decompression before reaching OXY?

18. What are the instructions after OXY 1?

19. What is the drill if the jet suffers an engine failure before reaching Yabrai?

20. Why does British Airways use imaginary waypoints in its flight plans?

21. What does the ghost waypoint “Hotel” mark?

Exercise 3.9.3 Are the following statements true (√) or false (×)? Correct the false ones.

1. The high terrain dictates special planning in case the flight has to direct to an alternative airfield.

2. The concerns are twofold.

3. Engine failure won’t force a descent to a lower altitude.

4. The cruising altitude and range on three engines are similar to the performance with all engines operating.

5. The real problem occurs if the jumbo were to lose a second engine.

6. Decompression would be the more critical consideration.

7. In case of pressurization, the oxygen masks will deploy automatically.

8. Oxygen masks give the passengers a source of breathable air until the jet can complete an emergency descent.

9. The air is dense at 14,000ft.

10. Descending is impossible in the area of high terrain.

11. The jumbo doesn’t carry enough oxygen to supply the passengers for a prolonged period of time.

12. Escape routes have been developed to take a jet into areas where the safety height is below 10,000ft.

13. The decision point for a pressurization emergency is known as OXY 2.

14. All waypoints are marked on the chart.

15. British Airways uses other imaginary waypoints in the flight plans to denote sections of the route where the safety altitude changes significantly.

16. There is a tactical planning chart that highlights the critical decision points and details the crew procedures to be followed for an engine failure or a decompression.

Exercise 3.9.4 Give English equivalents for the following words and word combinations.

Специальное планирование; в случае, если; уклониться на запасной аэродром; двойной; отказ двигателя; зависеть от …; вес самолета; окружающие, сопутствующие условия; безопасная высота; все двигатели работают; случаться, происходить; разгерметизация; кислородные маски; автоматически раскрываться; источник вдыхаемого воздуха; аварийное снижение; обычная процедура; плотный воздух; крейсерская высота; обеспечить; продолжительный период времени; иметь дело с чем-то, справиться с чем-то; аварийный трап; в общем количестве; аварийный маршрут; отмечать что-то на карте; или … или …; следовать по трассе; зависеть от; воображаемые, представляемые точки донесения по маршруту; значительно; продолжать полет в пункт назначения.

Exercise 3.9.5 What do the following abbreviations stand for?

NDB ft nm MSA

Exercise 3.9.6 Find in the text synonyms for the following words and expressions.

Aerodrome; coupled; rely upon; plane; engine fault (problem); jet’s progress; alike; happen; must; pressurization; experience; origin; accomplish; thick; to request; zone; contribute; extended; to deal with; whole; planning map; include; situated; return; keep the airway; an exercise; unreal waypoint; indicate.

Exercise 3.9.7 Match the word combinations and expressions in column A with those in column B.

A	В
1. ambient conditions	a. плотный воздух
2. to depend on smith	b. оставаться на ЭП
3. to suffer decompression	c. уклониться на запасной аэродром
4. oxygen masks	d. аварийный трап
5. for a prolonged period of time	e. окружающие (сопутствующие) условия
6. to remain at FL	f. зависеть от чего-то
7. dense air	g. кислородные маски
8. escape slide	h. завершить аварийное снижение
9. to complete an emergency descent	i. пострадать от разгерметизации
10. to divert to an alternate airfield	j. в течение продолжительного периода времени

Exercise 3.9.8 Fill in the gaps with the words from the text choosing from the ones given below.

1. The high terrain dictates special planning in case the flight has to _________ (fly, direct, divert) to an alternate airfield.

2. Engine _________ (breakdown, failure, loss) would force a descent to a lower altitude.

3. Lower altitude depends on the aircraft weight and _________ (surrounding, ambient, environmental) conditions.

4. The real problem _________ (happens, appears, occurs) if the plane loses an engine.

5. If the cabin _________ (experiences, undergoes, suffers) a loss of pressurisation, oxygen masks will deploy automatically.

6. Oxygen masks ___________ (give, provide, supply) the passengers a source of breathable air.

7. The _________ (common, ordinary, usual) procedure is to descend to the altitude where the air is dense.

8. The critical decision points and details of the crew procedures to be _________ (made, followed, fulfilled) for an engine failure or a decompression may be found in the tactical planning chart.

9. Waypoints are inserted in the flight plan and _________ (noted, marked, stated) on the chart.

10. The jet had to _________ (keep, follow, continue) airway A 596.

Exercise 3.9.9 Fill in the gaps with the related words.

1. The high terrain dictates special _________ in case the flight has to divert to an alternative airfield. (PLAN)

2. Oxygen masks give the passengers a source of __________ air. (BREATH)

3. Speedbird 25 received the __________ to continue flying to the Yabrai NDB. (INSTRUCT)

4. In case of pressurization, oxygen masks will diploy ________ .(AUTOMATIC)

5. The cruising altitude and range on three engines are similar to the _________ with all engines operating. (PERFORM)

6. The more critical __________ is decompression. (CONSIDER)

7. Oxygen masks do not carry enough oxygen to supply the passengers for a __________ period of time. (PROLONG)

8. Waypoints are __________ and _________ on the chart. (INSERT + MARK)

Exercise 3.9.10 Translate the following sentences into English.

1. Возвышенная местность диктует специальное планирование в случае, если воздушное судно должно уклониться на запасной аэродром.

2. Если случится отказ двигателя – это вызовет снижение на более низкую высоту.

3. Выбор высоты зависит от веса самолета и окружающих условий.

4. Самолет может выдерживать крейсерскую высоту на трех двигателях так же, как и при работе всех двигателей.

5. Очень серьезная аварийная ситуация происходит тогда, когда отказывают два двигателя.

6. Разгерметизация – более серьезная проблема.

7. Если случится разгерметизация, то кислородные маски выпускаются автоматически.

8. Кислородные маски обеспечивают пассажиров воздухом до тех пор, пока самолет не снизится до определенной высоты, где пассажирам не нужны маски.

9. Британские Авиалинии разработали аварийные (спасательные) маршруты, куда могут быть направлены самолеты и где безопасная высота ниже 10.000 футов.

10. Количество кислородных баллонов на каждый самолет увеличено на три штуки – в общем до 19 (штук).

11. На оборотной стороне карты полета есть описание процедур, которым должен следовать экипаж в случае отказа двигателя или разгерметизации.

12. В случае аварийной ситуации в случае разгерметизации следует направляться в точку ОКСИ 1.

13. Пункты следования занесены в план полета и отмечены на карте.

14. После точки ОКСИ 1 указания будут получены от диспетчера следовать на Дельта Янки и следовать по трассе А 596.

15. Британские Авиалинии используют различные воображаемые пункты в планах полетов чтобы определить участки маршрутов, где безопасные высоты значительно изменяются.

Exercise 3.9.11 Make up your own sentences using the following words and word combination.

Divert to an alternative airfield; engine failure; descent to a lower altitude; depend on; aircraft weight; ambient conditions; the jet’s good performance; real problem; occur; oxygen masks; deploy automatically; breathable air; complete an emergency descent; usual procedure; area of high terrain; prolonged period of time; engine failure; waypoints; turn back; oxygen bottles; highlight.

Exercise 3.9.12 Retell the text.