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时间:2010-09-08 00:33来源:蓝天飞行翻译 作者:admin
曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

• Environment Canada
• NASA
• FAA
• Transport Canada
• National Research Council of Canada
• SMECMA
• The Boeing Co.
• Airbus Ind.
• Pratt and Whitney Engines
• Honeywell Engines
• General Electric Engines
• Rolls Royce Engines
Canada
6
Location of engine events
Canada
Longitude
Latitude
-150 -100 -50 0 50 100 150
-80
-60
-40
-20
0
20
40
60
80
• high frequency of events in southeast Asia
7
Observations about meteorology
Canada
1. High altitude, cold temperature
2. Aircraft in the vicinity of convective clouds/thunderstorms
3. Significantly warmer than standard atmosphere
4. Visible moisture/ Instrument Meteorological Conditions (IMC)/ In cloud
5. Light to moderate turbulence
6. Precipitation on windscreen, often reported as rain
7. Aircraft total air temperature probe (TAT) anomaly
8. Lack of observations of significant airframe icing
9. No flight-radar echoes at the location and altitude of the aircraft engine
event (only large transport aircraft pilots queried)
8
TAT anomaly
􀂄 Error in TAT measurement thought to be caused by ice particle collecting and
blocking the airflow through the probe
􀂄 In commuter event below (glaciated cloud –26 C), occurs within 60 s of IWC
exceeding 0.5 gm-3, and clears within 30 s of IWC falling below 0.5 gm-3
􀂄 Good cue for flight in high IWC
Canada
9
•Satellite Infrared
sequence starting
5.5 hrs before
incident
• note convective
elements southwest
of Taiwan grow and
merge into massive
convective complex
• growth of bright
cloud tops in this
region indicate
potential for dense
ice crystal zones at
high altitude
Canada
Engine
event case
study
10
Engine event case study (cntd)
Figure shows heavy precipitation below aircraft altitude, obvious convection of fully
developed typhoon
Canada
11
The TAT anomaly from FDR data
-30 -20 -10 0 10 20 30
5000
10000
15000
20000
25000
30000
35000
40000
-50 -40 -30 -20 -10 0 10 20 30
5000
10000
15000
20000
25000
30000
35000
40000 (a) (b)
TAT freezing
engine event
Altitude (feet)
Total Air Temperature (C)
Aircraft climb
Aircraft descent
standard
atmosphere
~20 C warmer
than standard
atmosphere
engine event
Altitude (feet)
Static Air Temperature (C)
Aircraft climb
Aircraft descent
Static Air Temperature (a) and Total Air Temperature (b) measured during climb from Hong Kong
(black symbols) and during descent towards Taipei (red symbols), illustrating the TAT anomaly
observed before the engine event
Canada
12
The time sequence of the engine event
Time history of altitude and Total Air Temperature (TAT), surrounding the time of the
engine event at 12:52:58. The estimated Static Air Temperatures (SAT) are shown in
text at the top of the lower panel for reference. Note the time of powerloss is
identified in figure.
Canada
13
An industry measurement of an engine
event
Canada
-3 -3
22:10 22:20 22:30 22:40 22:50 23:00 23:10 23:20 23:30
Time (UTC)
0.0
0.5
1.0
1.5
IWC (gm )
1.0
1.1
1.2
1.3
Rosemount Ice Detector V
0
100
200
300
Ice Conc. (cm )
IWC est. from Nev. LWC
IWC est. from FSSP+2DC
Rosemount ice Detector V (trip ~ 8V)
FSSP concentration
ALLIED/BAE FLIGHT 850: 16 JUNE 1997 22:10:00-23:27:25
• BAe-146 test aircraft instrumented
for cloud microphysics
• successfully induced an engine
powerloss event orbiting in an anvil
downwind of a thunderstorm core
• no LWC measured, just moderately
high IWC up to ~2 gm-3
•Very small median mass diameters
•Our working hypothesis on what to
expect in deep convection (glaciated,
high IWC, small particles)
14
• Extensive study in 1950s by Royal
Aircraft Establishment to measure TWC
levels in equatorial deep convection
(Singapore, Darwin, Entebbe) –
measured values up to ~8 gm-3
• Not much since – mainly just
penetrations away from convective core
in the trailing anvil region
• Calculations of adiabatic IWC predict
 
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