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head wind 逆風,頂頭風。

head work

Based on the sha lo wan profiler data at 0740utc , the vertical shear at around 1 , 100 ft was close to 8 kt per 100 ft . although this was lower than the 8 kt per 100 ft which has been used in the windshear warning system at the old kai tak airport , the increase in head wind was nonetheless significant due to the steep climb angle 根據沙螺灣的氣流剖析儀在0740utc錄得的資料顯示,在約1 , 100尺的垂直切變接近每百尺每小時8海里。雖然此切變低于以往啟德機場的風切變警報系統所用的每百尺每小時8海里,但因為陡峭的爬升角度,令到逆風的增加變得顯著。

The shear experienced by the departing aircraft was due to vertical shear as the plane passed through the low level jet . based on the winds measured on - board a flight departing 8 minutes earlier , there was a rapid increase in head wind component , from 13 kt at 1 , 420 ft to 39 kt at 3 , 100 ft 起飛的飛機所遇到的風切變是由于該機經過低層急流的垂直切變所引致,根據一架在8分鐘前起飛的航機量度到的風速,顯示逆風由1 , 420尺的每小時13海里急速增加到在3 , 100尺的每小時39海里。

It lurks in the sky and when the time is right , it rushes towards the ground causing significant downdraughts and changes in head wind . microburst first coined by t . fujita , is so dangerous that every pilot would try to avoid it , especially during take - off and landing 隱藏在天空中,只待時機成熟就沖向地面,造成顯著的下沉氣流和逆風變化,這就是微下擊暴流。微下擊暴流這個現象的名稱由藤田首創。

Fig . 12 time series of head wind change relative to aircraft landing on runway 07l between the buoy and the anemometer at the western end of runway 07l . time and magnitude of the four windshear events are also indicated on the graph 圖12浮標氣象站及07l跑道西端風速表的逆風變化時間序列逆風為相對于降落07l跑道而言,圖中亦顯示了四個風切變報告的時間和風速。

Departing flights were climbing at very steep angles , 9 . 6 deg for the one shown above . as a result , the aircraft transit the low level jet very close to the end of the runway and the change in head wind was very rapid 起飛的航機以非常陡的角度爬升,以上提及的飛機用9 . 6度,因此飛機在接近跑道末端經過低空急流而所感受到的逆風轉變非常快。

Vertical velocity of the aircraft , vertical wind derived from flight parameters , head wind derived from on - board wind measurements and variation of on - board winds during the approach 、航機的垂直速度、由航機參數計算所得的垂直風速度、機上測風儀量度的逆風速度及航機在降落時遇到的風場變化。

Vertical velocity of the aircraft , vertical wind derived from flight parameters , head wind derived from on - board wind measurements and variation of on - board winds during the approach 航機的垂直速度由航機參數計算所得的垂直風速度機上測風儀量度的逆風速度及航機在降落時遇到的風場變化。

Fig . 12 time series of head wind change ( relative to aircraft landing on runway 07l ) between the buoy and the anemometer at the western end of runway 07l 圖12浮標氣象站及07l跑道西端風速表的逆風變化時間序列(逆風為相對于降落07l跑道而言) ,圖中亦顯示了四個風切變報告的時間和風速。

Fig . 12 time series of head wind change relative to aircraft landing on runway 07l between the buoy and the anemometer at the western end of runway 07l 圖12浮標氣象站及07l跑道西端風速表的逆風變化時間序列(逆風為相對于降落07l跑道而言) ,圖中亦顯示了四個風切變報告的時間和風速。

Based on the head wind measured on board , the lifting shear experienced by these two flights in the last 100 - 200 ft was less than 10 kt 根據機上所錄得的逆風資料,當時該兩班航機在100至200尺上空遇到上升型風切變,強度在每小時10海里以下。

It lurks in the sky and when the time is right , it rushes towards the ground causing significant downdraughts and changes in head wind 隱藏在天空中,只待時機成熟就沖向地面,造成顯著的下沉氣流和逆風變化,這就是微下擊暴流。

The transit of the plane through the northwest - southeast squall line was uneventful , and the head wind changes were not particularly high 飛機順利飛過從西北走向東南的颮線,逆風的轉變也不算劇烈。

As the plane exited the storm into the prevailing southwesterlies , there was a rapid increase in both the head wind and updraught 其后航機飛出暴雨區進入盛行西南風帶時,逆風和上升氣流均迅速加強。

Figure 5 shows the head wind recorded by five flights representative of those flights in the first episode 圖五所示的逆風,就是當第一次風切變現象出現時,受影響的其中五班航機所錄得的。

They all encountered an increase in head wind of around 10 - 15 kt in the last 100 feet before touchdown 這些航機全部在臨陸前的100尺上空遇上逆風增強,風速增強每小時10至15海里。

Eg . the entire ship paused and shuddered as the sails were taken aback by a sudden strong head wind 由于一陣強烈的頂頭風突然把帆吹翻過來,船一下子停住,不斷震動。

The variation of head wind with height for two flights landing at around 13utc is given in figure 6 圖六顯示在大約13utc兩班航機陸時錄得的逆風和高度變化。

The yacht had to beat about for several hours owing to the strong head winds 因為強烈的逆風,游艇在幾小時內不得不反復轉換航向。

I just found out she has a head wound 我只知道她頭部受傷