Blocked transmission

무전기 두 대가 동시에 송신하면 서로를 지워버립니다 — 그 "삐이" 소리가 blocked transmission. 잘못한 사람이 없어도 위험은 생겨요. 오늘의 원칙: 조각만 들었으면, 들은 척하지 말 것. 문법은 둘을 묶어 말하는 neither…nor / both…and입니다.

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1. Scenario

I was the First Officer of HL123, calling for taxi during the busiest departure push of the morning.

The ground frequency was completely saturated. When our taxi clearance finally came, another aircraft transmitted at exactly the same moment — both transmissions overlapped, and all we heard was a loud squeal with fragments inside it: "…runway 33… hold short…"

A fragment is not a clearance. We stayed where we were, waited for a gap, and called with our full callsign: "Ground, HL123 — say again, you were blocked." The second attempt was blocked again — the frequency was simply too busy, and neither station could hear the other.

At that point the controller took charge of the frequency. He transmitted, "All stations, standby," re-issued our clearance slowly with nothing else on the air, and got a clean readback. A few minutes later, ground was split onto a second frequency to spread the load, and the congestion disappeared.

We taxied out on the confirmed routing and departed normally. Nobody had made a mistake — and that is exactly why radio discipline matters.

2. At a Glance

English — During a busy departure push, our taxi clearance was blocked — two stations transmitted at once, and we caught only fragments through the squeal. We did not move. We waited for a gap and asked again: "Say again, you were blocked." When the second call was blocked too, the controller froze the frequency — "All stations, standby" — re-issued the clearance slowly, and later split ground onto a second frequency. The rule: never act on a partial clearance. Fragments plus assumptions are how taxi conflicts start.

한국어 — 아침 출발 러시에 우리 지상활주 허가가 블록됐습니다 — 두 국이 동시에 송신해 "삐이" 소리와 조각("…활주로 33… hold short…")만 들렸어요. 우리는 움직이지 않았습니다. 틈을 기다려 풀 콜사인으로 "Say again, you were blocked"를 보냈고, 두 번째도 블록되자 관제사가 주파수를 잡았습니다 — "All stations, standby" 후 천천히 재발부, 이어서 지상 주파수를 둘로 분리해 부하를 나눴죠. 원칙 — 조각 클리어런스로는 절대 행동하지 않는다. 조각+추측이 지상 충돌의 시작입니다.

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3. Key Verbs

block

뜻: (송신이) 막히다, 겹쳐 지워지다

• Our clearance was blocked by another transmission.
• The second call was blocked as well.

step on

뜻: (남의 송신을) 밟다, 겹쳐 송신하다

• Someone stepped on the controller's call.
• Wait for a gap so you do not step on anyone.

garble

뜻: (음성이) 뭉개지다

• The clearance came through garbled.
• A garbled call is treated as no call at all.

overlap

뜻: 겹치다

• Both transmissions overlapped completely.
• When calls overlap, only a squeal survives.

copy

뜻: 알아듣다, 수신하다

• We did not copy the full clearance.
• "HL123 did not copy — say again."

pause

뜻: 잠시 멈추다

• The controller paused the whole frequency.
• Traffic calls were paused with "all stations, standby."

repeat

뜻: 반복하다

• He repeated the clearance slowly, word by word.
• The routing was repeated with nothing else on the air.

split

뜻: (주파수·업무를) 분리하다

• Ground was split onto a second frequency.
• Splitting the load ended the congestion.

wait

뜻: 기다리다

• We waited for a gap before transmitting.
• Never transmit while another call is still going — wait.

act

뜻: (근거로) 행동하다

• We never act on a partial clearance.
• Do not act on fragments and assumptions.

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4. Key Expressions & Collocations

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5. Vocabulary

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6. Sentence Frames

빈칸만 갈아끼우면 다른 교신 문제 시나리오에도 그대로 씁니다.

• Our ____ was blocked by another transmission. → Our taxi clearance was blocked by another transmission.
• All we heard was ____ with fragments inside it. → All we heard was a loud squeal with fragments inside it.
• We caught only fragments, so we asked again instead of guessing. → (그대로 외워둘 만한 문장)
• Neither ____ nor ____ could hear ____. → Neither station nor the controller could hear the whole call.
• Both ____ and ____ ____ed at the same time. → Both we and another aircraft transmitted at the same time.

오늘의 표현 포인트 — "We caught only fragments, so we asked again instead of guessing." 조각만 들었고, 그래서 추측 대신 다시 물었다 — 이 한 문장이 오늘 판단의 전부입니다.

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7. Common Mistakes → Better Phrasing

한국인이 자주 쓰는 틀리거나 약한 표현을, 시험에서 통하는 표현으로 바꿔 익히세요.

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8. Grammar Point — neither … nor / both … and

둘을 한 문장으로 묶으면 상황 설명이 짧고 정확해집니다.

• Neither station nor the controller heard the whole call.
• Both we and another aircraft transmitted at the same time.
• The block was neither our fault nor theirs — just timing.

핵심: neither A nor B = A도 B도 아니다 / both A and B = A와 B 둘 다. "잘못한 사람은 없는데 위험은 생겼다"는 오늘 같은 상황을 말하는 데 딱입니다.

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9. Model Answer — Q1

"What happened to your aircraft? Explain the nature of the incident."

틀은 자유 — 무슨 일 → 어떻게 대처 → 결과 흐름이면 됩니다.

We were calling for taxi during the busiest departure push of the morning, and the ground frequency was completely saturated. When our taxi clearance finally came, another aircraft transmitted at exactly the same moment. Both calls overlapped, and all we heard was a loud squeal with fragments inside it — something about runway 33 and holding short.

A fragment is not a clearance, so we stayed where we were. We waited for a gap and called with our full callsign: "Ground, HL123 — say again, you were blocked." The second attempt was blocked as well; by then neither we nor the controller could get a clean word in.

So the controller took charge. He transmitted, "All stations, standby," re-issued our clearance slowly with an empty frequency, and got a clean readback from us. A few minutes later ground was split onto a second frequency, and the congestion simply disappeared.

We taxied out on the confirmed routing and departed normally. Nobody had actually made a mistake — which is exactly why the discipline matters. On a congested frequency, the safest words are the boring ones: "say again."

10. Model Answer — Q2

"How do you think ATC handled the situation? Could it have been handled differently?"

Q2 = ATC 평가로 의견 표현을 익히는 자리. 아래는 한 예시 — 외워서 그대로 쓰지 말고, 시작·마무리 표현은 자유롭게 바꿔 보세요.

My take: nobody did anything wrong, and it still nearly went wrong — so I judge ATC on how fast they broke that loop. On that count, they were good. After the second block the controller stopped fighting the congestion and froze it instead: "all stations, standby," then one slow, clean clearance with the frequency to himself. And the real fix — splitting ground onto a second frequency — followed within minutes and made the problem vanish.

The fair criticism is timing. It was the morning push; the saturation was predictable, and the split could have been opened before the rush instead of after two blocked calls. Once the second frequency was running, everything worked — which shows where the morning should have started.

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11. Follow-up Q&A

1. Why is acting on a partial clearance so dangerous? → Because you fill the missing words with what you expect — and on the ground, a wrong expectation points your aircraft at someone else's runway.
2. What actually makes the squeal? → Two radios transmitting at the same time cancel each other out — what you hear is the squeal, not either voice.
3. Why insist on the full callsign when it is busy? → Congestion is exactly when half-heard calls get taken by the wrong aircraft. The callsign is what stops that.
4. What if you are not sure a clearance was meant for you? → Confirm before acting: "Was that for HL123?" One short question beats one wrong turn.

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12. Shadowing Sentences

각 문장을 3~5번 소리 내어 따라 하세요.

1. The ground frequency was completely saturated.
2. Another aircraft transmitted at exactly the same moment.
3. All we heard was a loud squeal with fragments inside it.
4. A fragment is not a clearance.
5. We waited for a gap before transmitting.
6. Ground, HL123 — say again, you were blocked.
7. Neither we nor the controller could get a clean word in.
8. All stations, standby.
9. Ground was split onto a second frequency.
10. We caught only fragments, so we asked again instead of guessing.

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