Lionair plane down in Bali.
For me I would say missed approaches occur about once every three to four hundred landings, roughly one a year. Most are because of aircraft not clearing the runway. Last one was because a CRJ cleared for takeoff did not like the weather on his departure route. Needless to say the tower was accomodating in allowing us to deviate from the standard missed approach.
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Lederhosen,
I agree 100% I can't remember the last time I executed a "real" missed approach when not in the simulator.
It's something we all ought to brief about prior to beginning the approach, especially when the Wx is at or near minimums.
I agree 100% I can't remember the last time I executed a "real" missed approach when not in the simulator.
It's something we all ought to brief about prior to beginning the approach, especially when the Wx is at or near minimums.
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Originally Posted by Hotel Tango
Quote:
Sounds like cr@p pilots at a cr@p airline
Based on what factual evidence White Knight?
Sounds like cr@p pilots at a cr@p airline
Based on what factual evidence White Knight?
@400 ft AGL - choose an appropriate roll mode (LNAV or HDG)
Good summary, however the above is not required if 'TOGA to LNAV' is available.
Last edited by JPJP; 23rd Apr 2013 at 17:46.
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JPJP: It's intentionally written that way because not all B737's have LNAV available as a (pre-)armed mode, i.e. prior to initiating a go-around, and therein require that the roll mode is 'selected', and accordingly it is hoped that those whom fly those types might still find this 'generic' advice useful too...of course in the NG it's pre-armed, though always assuming that the missed approach is indeed available (programmed) in the FMC via ones navigation performance engineering department and an example where it wouldn't be, being an airfield which has not been pre-programmed into your FMC in terms of approach & missed-approach tracks (& vertical profiles), i.e. just the 'blue circle' and nothing else and / or maybe not even the blue circle?!
Last edited by Old King Coal; 23rd Apr 2013 at 19:08.
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we are over complicating things
the last time I did a missed approach it was in full, glorious day VMC. KLGA...traffic on the runway (31`) having just flown the long island expressway visual...
tower...go around, maintain 2500ft.
us...roger
tower...stop climb at 1500 feet...seaplane transiting at 2000'.
ME grabbing throttless and trying not to go negative g (we got the word at 1300'.
lesson...all go arounds involve pulling up, adding power, configuring and being ready for anything.
not punching buttons on an FMC.
Looking out the window helps alot too.
while making an autoland or low vis, i can see wanting electronics...but when navigating comes before aviating...something is wrong.
tower...go around, maintain 2500ft.
us...roger
tower...stop climb at 1500 feet...seaplane transiting at 2000'.
ME grabbing throttless and trying not to go negative g (we got the word at 1300'.
lesson...all go arounds involve pulling up, adding power, configuring and being ready for anything.
not punching buttons on an FMC.
Looking out the window helps alot too.
while making an autoland or low vis, i can see wanting electronics...but when navigating comes before aviating...something is wrong.
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Originally Posted by 7strokeroll
lesson...all go arounds involve pulling up, adding power, configuring and being ready for anything
But of course; if you're a Yank you wouldn't understand thisDISCLAIMER: No idea about Seattle's technique for GA
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lesson...all go arounds involve pulling up, adding power, configuring and being ready for anything.
No - you would carry out the Go Around at the time of the ATC request. There is no requirement to continue to minima if you or ATC require the discontinuation of the approach.
'SevenStrokeRoll' does raise an excellent point though; At airports like LaGuardia (New York) or Midway (Chicago), where the level off altitudes for a missed approach are typically low, some thinking is required. In this case I prefer one "click" on the TOGA button. This provides a more manageable rate of climb. The obvious safety caveats being - VFR, Day, no obstacles and a non critical altitude at which the missed approach is commenced.
'SevenStrokeRoll' does raise an excellent point though; At airports like LaGuardia (New York) or Midway (Chicago), where the level off altitudes for a missed approach are typically low, some thinking is required. In this case I prefer one "click" on the TOGA button. This provides a more manageable rate of climb. The obvious safety caveats being - VFR, Day, no obstacles and a non critical altitude at which the missed approach is commenced.
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Philipat, you appear to have missed my question.
Originally Posted by philipat
Actually, I do believe that the accident has already been very well explained herein
Originally Posted by philipat
I still do NOT believe that Windshear/Microburst conditions existed at the time of the accident.
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Perhaps you could explain what Windshear/Microburst conditions are?
forecasting methodologies
There is at present an insufficient observational database from which to develop a comprehensive forecasting scheme for microbursts; however, there are enough data from the Joint Airport Weather Studies (JAWS) project on which to base and design an objective forecasting algorithm for dry microbursts. Data from the MIcroburst and Severe Thunderstorm (MIST) project plus case studies of the Gulf Coast and Florida area provide sounding based thresholds for wet microbursts. The development of a comprehensive forecast scheme for microbursts is for the moment on hold, until the required field project data are taken.
Microbursts in classic severe storm environments
The aircraft accident rate due to microbursts in association with classic severe local storms is practically nonexistent for commercial aviation, since the system is apparently well designed to protect passenger jets against well-organized, long-lived, and highly reflecting storms and therefore automatically protects aircraft from any microburst components of these storms. By simply avoiding classic severe storm types, such as squall lines and supercells, pilots are already avoiding any microburst components of these storms. However, aircraft are not well protected from wet and dry microbursts that are an unexpected component of isolated airmass-type thunderstorms, and rainshowers.
The predictability of microbursts in a dry environment
Krum (1954) first described the typical sounding associated with dry thunderstorms that produce strong downdrafts. Prediction of dry microbursts from local soundings was explored qualitatively first by Brown et al. (1982) then by Wakimoto (1985) based on JAWS (Joint Airport Windshear Studies) project data. A preliminary, quantitative prediction scheme also based on JAWS project data was proposed by Caracena et al. (1983a) and Caracena and Flueck (1986 and 1987a and b), demonstrating that the virga-type microbursts in that form in dry sub-cloud environments can be forecast in terms of upper air data. What remained to be found were a means of forecasting microbursts in a wet enviroment in association with heavy rain. These were the type of conditions involved at New Orleans International Airport at 21 10 UTC 9 July 1982, when Pan American Airways Flight 759 crashed after attempting to take off through a wet microburst (Caracena et al., 1983b).
Predicting wet microbursts
Atkins and Wakimoto (1991) analyzing data from the 1986 MIST (MIcroburst and Severe Thunderstorm) project conducted in northern Alabama found that in all five days when wet microburst occurred, the equivalent potential temperature differences between the surface value and the minimum aloft were 20 deg K or greater. On the other three days with thunderstorms, but without microbursts, there were equivalent potential temperature differences of 13 deg K or less. Atkins and Wakimoto (1991) also examined data from other well documented wet microburst cases, such as happened near Chicago (Fujita 1985), near Edmund, Oklahoma (Eilts and Doviak 1987), and southern Florida (Caracena and Maier 1987). They found that in all these microburst cases, the equivalent potential differences were greater than 20 deg K.
There is at present an insufficient observational database from which to develop a comprehensive forecasting scheme for microbursts; however, there are enough data from the Joint Airport Weather Studies (JAWS) project on which to base and design an objective forecasting algorithm for dry microbursts. Data from the MIcroburst and Severe Thunderstorm (MIST) project plus case studies of the Gulf Coast and Florida area provide sounding based thresholds for wet microbursts. The development of a comprehensive forecast scheme for microbursts is for the moment on hold, until the required field project data are taken.
Microbursts in classic severe storm environments
The aircraft accident rate due to microbursts in association with classic severe local storms is practically nonexistent for commercial aviation, since the system is apparently well designed to protect passenger jets against well-organized, long-lived, and highly reflecting storms and therefore automatically protects aircraft from any microburst components of these storms. By simply avoiding classic severe storm types, such as squall lines and supercells, pilots are already avoiding any microburst components of these storms. However, aircraft are not well protected from wet and dry microbursts that are an unexpected component of isolated airmass-type thunderstorms, and rainshowers.
The predictability of microbursts in a dry environment
Krum (1954) first described the typical sounding associated with dry thunderstorms that produce strong downdrafts. Prediction of dry microbursts from local soundings was explored qualitatively first by Brown et al. (1982) then by Wakimoto (1985) based on JAWS (Joint Airport Windshear Studies) project data. A preliminary, quantitative prediction scheme also based on JAWS project data was proposed by Caracena et al. (1983a) and Caracena and Flueck (1986 and 1987a and b), demonstrating that the virga-type microbursts in that form in dry sub-cloud environments can be forecast in terms of upper air data. What remained to be found were a means of forecasting microbursts in a wet enviroment in association with heavy rain. These were the type of conditions involved at New Orleans International Airport at 21 10 UTC 9 July 1982, when Pan American Airways Flight 759 crashed after attempting to take off through a wet microburst (Caracena et al., 1983b).
Predicting wet microbursts
Atkins and Wakimoto (1991) analyzing data from the 1986 MIST (MIcroburst and Severe Thunderstorm) project conducted in northern Alabama found that in all five days when wet microburst occurred, the equivalent potential temperature differences between the surface value and the minimum aloft were 20 deg K or greater. On the other three days with thunderstorms, but without microbursts, there were equivalent potential temperature differences of 13 deg K or less. Atkins and Wakimoto (1991) also examined data from other well documented wet microburst cases, such as happened near Chicago (Fujita 1985), near Edmund, Oklahoma (Eilts and Doviak 1987), and southern Florida (Caracena and Maier 1987). They found that in all these microburst cases, the equivalent potential differences were greater than 20 deg K.
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JP
So, when you go missed, you dont follow the missed approach procedure?
No - you would carry out the Go Around at the time of the ATC request. There is no requirement to continue to minima if you or ATC require the discontinuation of the approach.
Originally Posted by FlightpathOBN
So, when you go missed, you dont follow the missed approach procedure?
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This part?
"If ATC has not issued specific instructions prior to the approach and a missed approach is executed, the pilot must follow the (default) missed approach procedure published on the approach plate for that runway. "
"If ATC has not issued specific instructions prior to the approach and a missed approach is executed, the pilot must follow the (default) missed approach procedure published on the approach plate for that runway. "