Departure clearance, climb gradient and a traffic alert
You are flying a DA40, B-HKC, IFR from Hong Kong International (VHHH) to Kaohsiung. At 08:05, before start, you call Delivery: Hong Kong Delivery, B-HKC, DA40 at the Business Aviation Centre, request IFR clearance to Kaohsiung. Delivery replies: B-HKC, cleared to Kaohsiung via the BEKOL 2A departure, flight planned route, climb initially to 5,000 ft, expect flight level 180 ten minutes after departure, squawk 4702, contact Hong Kong Approach when airborne. The BEKOL 2A requires a minimum climb gradient of 6% to 3,000 ft, and your aircraft, fully fuelled with two adults on board, has been showing about 450 ft/min at 80 kt in the climb - roughly 5.5%. After take-off, on the Approach frequency: B-HKC, radar contact, climb to flight level 180, traffic alert, turn right heading 120, climb 6,000 ft, opposite direction traffic 12 o'clock, 4 miles, a Boeing 737.
1. Give the full readback of the departure clearance and explain what `expect flight level 180 ten minutes after departure` does and does not authorise.
Read the worked answer
- Readback:
B-HKC, cleared to Kaohsiung via the BEKOL 2A departure, flight planned route, initially 5,000 ft, expect flight level 180 ten minutes after departure, squawk four seven zero two, B-HKC. - Elements that must be read back: clearance limit (Kaohsiung), route and SID designator, initial level, squawk, and the frequency (good practice even where not mandatory).
Cleared to Kaohsiungis your IFR clearance; the SID is the route to the first point and must be flown as published, including its climb gradient. Expect flight level 180 ...is information about the likely onward clearance. It is not a clearance to climb to flight level 180. You level off at 5,000 ft, or at whatever level ATC has actually cleared you to, and wait for an explicit climb clearance, which you then read back.- If in doubt, ask:
B-HKC, confirm cleared to flight level 180?Never treat an expected level as a cleared level - this is one of the classic clearance-readback errors.
2. You realise your aircraft cannot meet the published 6% climb gradient for the BEKOL 2A. What should you do, and what phraseology should you use?
Read the worked answer
- Recognise it on the ground, not in the air. The published gradient is an obstacle- and procedure-design requirement, not a target. If you cannot achieve it, the SID as cleared is not usable by you.
- Tell ATC before departure:
B-HKC, unable the BEKOL 2A due to climb performance, request an alternative departure.Delivery or Ground will coordinate a different SID, a vectored departure, or a delay. - If you discover it airborne:
B-HKC, unable to maintain the required climb gradient, request vectors or an alternative routing.Tell ATC immediately so they can protect terrain and traffic; do not simply fly a shallower climb in IMC and say nothing. - Practical fixes: reduce weight (fuel or payload), wait for cooler conditions, or accept the delay.
About 5.5%against a 6% requirement is within the normal scatter caused by temperature, density altitude and technique - treat it ascannot guarantee 6%, not asclose enough.
3. On the Approach frequency you receive: `B-HKC, traffic alert, turn right heading 120, climb 6,000 ft, opposite direction traffic 12 o'clock, 4 miles, a Boeing 737.` Give your readback and set out your actions.
Read the worked answer
- Readback, short and immediate:
B-HKC, turning right heading 120, climbing 6,000 ft.Read back only what you are actually doing. - Act first: turn right onto 120° at a normal rate and start the climb, respecting engine limits, then transmit. A traffic alert is an avoiding-action instruction, not a suggestion.
- Look out. The DA40 has no TCAS. The 737 is opposite direction; with roughly 370 kt of closure, 4 nm is about 40 seconds. Scan above and below as well as ahead - the vertical separation you are given may put it close in height.
- If you cannot comply (engine temperature, turbulence, performance), say so at once:
B-HKC, unable, ...and state what you can do. Silence is the one unacceptable response. - Afterwards: do not resume your own navigation or level until ATC clears you to; expect a new heading and level once the conflict is resolved.