Weather Radar Usage Boeing question
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Smithy:
[quote]Cold-soaking a radar at -40C for a period of time and then powering it on (therefore heating it up) will subject the components to significant thermal stress and will very quickly cause failure. /QUOTE]
Astute avionics manufacturers have always stressed incoming components at . . . . -40C . ., to knock out the ones that will fail prematurely. (That's part of why avionics are so expensive.) Wx radar antennas are designed to operate either occasionally or continuously at altitude, whether started warm or cold. Typically they average more than 10,000 hours flight time between unscheduled removals.
Some airlines automatically remove the antennas for lubrication and replacement of components that wear out at less than 10,000 hours, so their MTBUR, Mean Time Between Unscheduled Removals is much higher. Running the radar continuously will wear out the antenna pointing mechanism sooner, guaranteed.
The Wx radar transceiver has no moving parts, and is inside the pressure vessel in transport category aircraft, so not subject to extreme temperatures, of course.
How much does it cost to operate the Wx radar? Probably on the order of $1 per flight hour.
Some pilots find the radar return on the Nav Display to be a nuisance, and turn the intensity down to 0. It would be better to just turn it off.
Historically, UAL has been the only carrier to provide adequate Wx radar training to pilots.
GB
[quote]Cold-soaking a radar at -40C for a period of time and then powering it on (therefore heating it up) will subject the components to significant thermal stress and will very quickly cause failure. /QUOTE]
Astute avionics manufacturers have always stressed incoming components at . . . . -40C . ., to knock out the ones that will fail prematurely. (That's part of why avionics are so expensive.) Wx radar antennas are designed to operate either occasionally or continuously at altitude, whether started warm or cold. Typically they average more than 10,000 hours flight time between unscheduled removals.
Some airlines automatically remove the antennas for lubrication and replacement of components that wear out at less than 10,000 hours, so their MTBUR, Mean Time Between Unscheduled Removals is much higher. Running the radar continuously will wear out the antenna pointing mechanism sooner, guaranteed.
The Wx radar transceiver has no moving parts, and is inside the pressure vessel in transport category aircraft, so not subject to extreme temperatures, of course.
How much does it cost to operate the Wx radar? Probably on the order of $1 per flight hour.
Some pilots find the radar return on the Nav Display to be a nuisance, and turn the intensity down to 0. It would be better to just turn it off.
Historically, UAL has been the only carrier to provide adequate Wx radar training to pilots.
GB
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...As a radar engineer...
Furthermore, previously two Aircraft Engineers from AirXXs provided the same info as Smithy.
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What is an Engineer?
The rest of the world seems to use the name "engineer" for jobs which in the US are called mechanics or technicians.
How do you all distinguish between:
the guy who conceptualizes a new Wx radar system..
the guy who designs the innards of the Wx radar components..
the guy who lays out the wiring and mechanical installation of the weather radar system..
the guy who provides technical interface between the manufacturer and the user..
the guy who troubleshoots and replaces a wx radar LRU, Line Replaceable Unit..
the guy who repairs the LRU..
??
GB
How do you all distinguish between:
the guy who conceptualizes a new Wx radar system..
the guy who designs the innards of the Wx radar components..
the guy who lays out the wiring and mechanical installation of the weather radar system..
the guy who provides technical interface between the manufacturer and the user..
the guy who troubleshoots and replaces a wx radar LRU, Line Replaceable Unit..
the guy who repairs the LRU..
??
GB
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How do you all distinguish between:
the guy who designs the innards of the Wx radar components = Engineer
the guy who lays out the wiring and mechanical installation of the weather radar system = Assembler
the guy who provides technical interface between the manufacturer and the user = Support Representative
the guy who troubleshoots and replaces a wx radar LRU, Line Replaceable Unit = Aircraft Line Maintenance
the guy who repairs the LRU = Avionics Technician
That was easy. Next question?
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Thanks, Pappy. However, for most of them you provided the job description, not job title. For example, "Aircraft Line Maintenance" seems to be called Engineer in much of the English speaking world.
The guy making drawings, Engineering Orders and diagrams in the Engineering Dept. of an airline is what you call an assembler? I guess my English didn't translate. This is who I meant when I wrote, "Lays out." Sorry.
GB
The guy making drawings, Engineering Orders and diagrams in the Engineering Dept. of an airline is what you call an assembler? I guess my English didn't translate. This is who I meant when I wrote, "Lays out." Sorry.
GB
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BGA
Our Airbus (A-320) FCOM says the following in the Taxi checks
RADAR (if required) - ON
My understanding is if Airbus wanted the Radar to be ON all the time, they would not have written (If Required)
As mentioned earlier, these radars have a lot of moving parts and all of them have a MTBF. So by switching them Off when not needed is prudent.
So keep the radar ON for Takeoff but when settled in the climb/cruise and with unlimited visibility and with not a cloud in sight, it is quite Ok to switch it off
My two cents
Our Airbus (A-320) FCOM says the following in the Taxi checks
RADAR (if required) - ON
My understanding is if Airbus wanted the Radar to be ON all the time, they would not have written (If Required)
As mentioned earlier, these radars have a lot of moving parts and all of them have a MTBF. So by switching them Off when not needed is prudent.
So keep the radar ON for Takeoff but when settled in the climb/cruise and with unlimited visibility and with not a cloud in sight, it is quite Ok to switch it off
My two cents
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Greybeard
Indeed you are correct, avionics manufacturers employ an environmental stress testing in order to "weed out" weaker components and bring out other issues e.g. poor soldering. However issues can still appear post-test ater the unit has left the factory floor and is in service.
What kills electronics is thermal cycling - rapid heating up and cooling down. The most common way this can happen is the continuous cycling of power - i.e. switching on and off. Most failures occur at switch-on; at switch-on there are brief spikes of voltage and current which unavoidably over time damage the components, eventually causing failure. Obviously switching on-and-off also causes the components to heat up and then cool down again respectively; even in mil-grade components this causes damage over the long-term.
An interesting point to note is the decreasing availablility of mil-spec components; both suppliers and customers are growing increasingly wary of the high price (and, for suppliers, the low demand and hence small market) of mil-spec components, so increasingly avionics manufacturers are using mass-produced commercially-available components which can be found in anything from home computers to alarm clocks, and hence not spec'd to the more extreme temperature tolerances that mil-spec components have. Beancounters brilliance of course. Another reason why the free-market isn't always the answer to everything, despite what others think
With this in mind, it is easy to see why it is not a very good idea to continuously switch a radar on and off when cruising at FL300+ and the OAT is minus f-ing cold. Doing so on a regular basis over time will stress the radar components and will ensure an early visit to the workshop or a return to the factory. The radar installations I deal with are still in non-air-conditioned/nonpressurised environments (although typically processing equipment tends to be otherwise), although they usually have their own cooling apparatus for operation at higher ambient temperatures.
Smithy
Indeed you are correct, avionics manufacturers employ an environmental stress testing in order to "weed out" weaker components and bring out other issues e.g. poor soldering. However issues can still appear post-test ater the unit has left the factory floor and is in service.
What kills electronics is thermal cycling - rapid heating up and cooling down. The most common way this can happen is the continuous cycling of power - i.e. switching on and off. Most failures occur at switch-on; at switch-on there are brief spikes of voltage and current which unavoidably over time damage the components, eventually causing failure. Obviously switching on-and-off also causes the components to heat up and then cool down again respectively; even in mil-grade components this causes damage over the long-term.
An interesting point to note is the decreasing availablility of mil-spec components; both suppliers and customers are growing increasingly wary of the high price (and, for suppliers, the low demand and hence small market) of mil-spec components, so increasingly avionics manufacturers are using mass-produced commercially-available components which can be found in anything from home computers to alarm clocks, and hence not spec'd to the more extreme temperature tolerances that mil-spec components have. Beancounters brilliance of course. Another reason why the free-market isn't always the answer to everything, despite what others think
With this in mind, it is easy to see why it is not a very good idea to continuously switch a radar on and off when cruising at FL300+ and the OAT is minus f-ing cold. Doing so on a regular basis over time will stress the radar components and will ensure an early visit to the workshop or a return to the factory. The radar installations I deal with are still in non-air-conditioned/nonpressurised environments (although typically processing equipment tends to be otherwise), although they usually have their own cooling apparatus for operation at higher ambient temperatures.
Smithy
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Thanks, Smithy.
Lack of mil-spec components means more incoming inspection, including thermal cycling, required to achieve a mil-spec equivalent.
The small amount of heat generated by the electronics in a really cold Wx radar antenna isn't going to raise temperatures very much.
By definition, an airplane is a group of compromises flying in close formation, and the Wx radar antenna is, too. You have to balance the increase in failure rate of the electrical components from power cycles, vs the additional wear of the mechanical components if operated continuously. If the antenna is the older design with no electronics, then mechanical wear is the only factor.
As I alluded earlier, the Wx radar system is reliable enough that operational considerations take precedence over reliability. Probably most US airlines never turn on the radar except at night or when convective activity is visible. If it were required all the time, there would be no on/off switch on the fright deck. Fully half the Wx radar removals in the US occur in TS season, mostly in August.
Back to the 767: the Wx radar is powered only when a pilot has pushed the WX button on his EFIS control panel for display on his EHSI.
GB
Lack of mil-spec components means more incoming inspection, including thermal cycling, required to achieve a mil-spec equivalent.
The small amount of heat generated by the electronics in a really cold Wx radar antenna isn't going to raise temperatures very much.
By definition, an airplane is a group of compromises flying in close formation, and the Wx radar antenna is, too. You have to balance the increase in failure rate of the electrical components from power cycles, vs the additional wear of the mechanical components if operated continuously. If the antenna is the older design with no electronics, then mechanical wear is the only factor.
As I alluded earlier, the Wx radar system is reliable enough that operational considerations take precedence over reliability. Probably most US airlines never turn on the radar except at night or when convective activity is visible. If it were required all the time, there would be no on/off switch on the fright deck. Fully half the Wx radar removals in the US occur in TS season, mostly in August.
Back to the 767: the Wx radar is powered only when a pilot has pushed the WX button on his EFIS control panel for display on his EHSI.
GB
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I'm with Pappy on this. As I understand it in the past when we first got wx radar it used lots of power and several a/c in the circuit at the same time meant LOTS of rf which could interfere with the old ATC radars (Smithy can you confirm/deny?)
When I ask other pilots why the switch it off none has ever been able to answer.
Generally its a very badly taught subject in ground school (if its taught at all!)
its free! do you switch off the ADF just because you aren't using it?
When I ask other pilots why the switch it off none has ever been able to answer.
Generally its a very badly taught subject in ground school (if its taught at all!)
its free! do you switch off the ADF just because you aren't using it?
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Hi JHN,
No, but I think the comparison is not so relevant. The ADF that you mention is a mean of navigation and in modern airplanes you cannot "switch it off" unless you enter no frequency in it, but again it is not off, just not tuned.
In general you leave something off when it is not required, e.g anti ice, ignition, backup hydraulic pumps (electric or engine driven depends on airplanes), etc..
My opinion is that the is not a single way of thinking about that kind of subjects, what is relevant is the result you get in the end
its free! do you switch off the ADF just because you aren't using it?
When I ask other pilots why the switch it off none has ever been able to answer.
My opinion is that the is not a single way of thinking about that kind of subjects, what is relevant is the result you get in the end
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JHN
Yes other radar transmissions can appear if the Rx is tuned to the same frequency, e.g. if two aircraft are using, for example, X-band radars that transmit (and hence receive) at the same frequency and let's say that they are facing each other, both aircraft's radars would receive each other's transmission. Can make for some interesting effects on the PPI
Graybeard
Cheers, no problem. The components that suffer most tend to be power supply circuitry and any processing circuits, which can get very hot quickly. You are entirely correct in what you say however.
Smithy
Yes other radar transmissions can appear if the Rx is tuned to the same frequency, e.g. if two aircraft are using, for example, X-band radars that transmit (and hence receive) at the same frequency and let's say that they are facing each other, both aircraft's radars would receive each other's transmission. Can make for some interesting effects on the PPI
Graybeard
Cheers, no problem. The components that suffer most tend to be power supply circuitry and any processing circuits, which can get very hot quickly. You are entirely correct in what you say however.
Smithy
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Graybeard sir, I’m sure that you meant no offence/offense regarding the term ‘engineer’, but speaking as a UK CAA Licensed Engineer may I make a few points here?
In the 1980s It took me 7 years of study to gain licenses in TEN avionics subjects with the UK CAA. (I was no slouch, and passed every exam first time). The system has been simplified now, but it still requires a great deal of study and dedication. In an essay question, you’d be expected sketch and describe the workings of things like a radar Tx/Rx etc, and even if you passed this exam, you then had an oral examination with a CAA Surveyor who would quickly show you the door if you did not know your stuff. I know it’s only a word, but most technicians and mechanics have never had to go through all of this, and their level of knowledge and responsibility is not in the same league. Oh, and of course you need to stay up to date as far as modern avionics systems are concerned as well, the improvements in avionics systems since I gained my licenses are both fascinating and dramatic. Pappy’s explanation here is a little of an over simplification too I’m afraid Aircraft Line Mtce is an area, not a person, the guys who conceptualise and design the system are both Design Engineers. Guys, please do not pigeon hole people without knowing your pigeons. Moan over.
GB, Your point regarding the Tx/Rx itself being in a stable environment is of course correct, but as far as I recall my airline has no policy of routinely removing the scanner assembly for lubrication, and our MTBF is still extremely high. And just like the 767, the '400' and 777 systems are also only swithed on when you hit the button
Returning to the subject of radar system output power, I seem to remember that the old RCA system was about 60Kw peak output power, whereas the modern systems (Bendix etc) are around 100 Watts peak. As long as you are sitting BEHIND either system you are perfectly safe. (Can not recall any instances of ATC radar interference though). A point of interest regarding the older high power systems; if the aircraft in question flew at an extremely high cruise altitude, pressurising the waveguide system up to the scanner was absolutely essential. (You typically would used cabin air at the Tx/Rx end, and the fwd pressure seal would be maintained by a Mylar sheet over the flat-plate scanner). Even a small tear in this sheet would result in severe arc-over within the waveguide, rendering both radar systems useless. (I’ve seen the results, it’s as if someone has taken a welding torch to the inside of the waveguide). When the Bendix system was added as a retrofit to this aircraft, there was never another instance of waveguide arc-over.
I tend to agree with Capt Smithy; you are going to do more long-term harm to any system by regularly cycling the power, aircraft systems in general are far happier when they are left running, but particularly cycling a radar system on and off at cruise altitudes is never a good idea. Your radar system is there to help PROTECT you, why fly with your zipper undone?
In the 1980s It took me 7 years of study to gain licenses in TEN avionics subjects with the UK CAA. (I was no slouch, and passed every exam first time). The system has been simplified now, but it still requires a great deal of study and dedication. In an essay question, you’d be expected sketch and describe the workings of things like a radar Tx/Rx etc, and even if you passed this exam, you then had an oral examination with a CAA Surveyor who would quickly show you the door if you did not know your stuff. I know it’s only a word, but most technicians and mechanics have never had to go through all of this, and their level of knowledge and responsibility is not in the same league. Oh, and of course you need to stay up to date as far as modern avionics systems are concerned as well, the improvements in avionics systems since I gained my licenses are both fascinating and dramatic. Pappy’s explanation here is a little of an over simplification too I’m afraid Aircraft Line Mtce is an area, not a person, the guys who conceptualise and design the system are both Design Engineers. Guys, please do not pigeon hole people without knowing your pigeons. Moan over.
GB, Your point regarding the Tx/Rx itself being in a stable environment is of course correct, but as far as I recall my airline has no policy of routinely removing the scanner assembly for lubrication, and our MTBF is still extremely high. And just like the 767, the '400' and 777 systems are also only swithed on when you hit the button
Returning to the subject of radar system output power, I seem to remember that the old RCA system was about 60Kw peak output power, whereas the modern systems (Bendix etc) are around 100 Watts peak. As long as you are sitting BEHIND either system you are perfectly safe. (Can not recall any instances of ATC radar interference though). A point of interest regarding the older high power systems; if the aircraft in question flew at an extremely high cruise altitude, pressurising the waveguide system up to the scanner was absolutely essential. (You typically would used cabin air at the Tx/Rx end, and the fwd pressure seal would be maintained by a Mylar sheet over the flat-plate scanner). Even a small tear in this sheet would result in severe arc-over within the waveguide, rendering both radar systems useless. (I’ve seen the results, it’s as if someone has taken a welding torch to the inside of the waveguide). When the Bendix system was added as a retrofit to this aircraft, there was never another instance of waveguide arc-over.
I tend to agree with Capt Smithy; you are going to do more long-term harm to any system by regularly cycling the power, aircraft systems in general are far happier when they are left running, but particularly cycling a radar system on and off at cruise altitudes is never a good idea. Your radar system is there to help PROTECT you, why fly with your zipper undone?
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M2dude....question for you...
M2dude,
I was curious....I'll ask you, since you seem to be switched on regarding
RADAR....in the new RADARs, you are warned to be at least 15 meters from the transmitting antenna. (Airbus says not to turn it on when on the ground, if there are people or things within 15 meters.)
But, regarding the old stuff....like the 60 KW stuff you mentioned....what is the minimum safe distance to be when such a RADAR is transmitting?
I've always thought it was 100 meters....but someone, recently, said it was much less.
Just curious....
Fly safe,
PantLoad
I was curious....I'll ask you, since you seem to be switched on regarding
RADAR....in the new RADARs, you are warned to be at least 15 meters from the transmitting antenna. (Airbus says not to turn it on when on the ground, if there are people or things within 15 meters.)
But, regarding the old stuff....like the 60 KW stuff you mentioned....what is the minimum safe distance to be when such a RADAR is transmitting?
I've always thought it was 100 meters....but someone, recently, said it was much less.
Just curious....
Fly safe,
PantLoad
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Hi PantLoad, I recall that 100 (ish) feet was about the safe minimum. In military high-power radars/ecm systems, the distance is farther. There is a huge amount of output power here, concentrated in a very narrow beam.
Last edited by M2dude; 29th Jan 2010 at 11:41.
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Thanks for the explanation, M2dude, and please excuse the thread drift, as I was confused in prior posts who was what kind of engineer. I'm truly asking to learn. As you must know, signing for return to service in the US requires a licensed A&P, Aircraft & Powerplant mechanic. Engineers in the US usually have more theoretical education than A&P, but are not licensed. They are the design engineers at the manufacturers and the service engineers at airlines who design and document repairs and modifications. Are only your licensed engineers authorized to release for return to service, or do you have other levels of mechanics and technicians with authorization?
Still, a person calling himself engineer without specifying what type confuses me.
Oh, I'm sure most of the airlines have their radar antenna maintenance "on condition," rather than on "hard time." I knew one FAA Principal Avionics Inspector who required radar antenna overhaul at 9,000 hours, as he insisted, rightly, that mechanical parts wear out. Their MTBUR, Mean Time Between Unscheduled Removals, was much higher than other airlines as a result.
As for too many early radars in the area causing ATC radar problems: highly unlikely, as ATC radar has been S band, around 2 GHz, like your microwave oven, while the early RCA radars were C band, above 5 GHz. More likely, too many transponder replies were overloading ATC. That was one reason for the ALT OFF switch on the transponder control panel.
The RCA radars of the 1960s and 70s, AVQ-10 and AVQ-30 and the Bendix RDR-1E and RDR-1F of the same era - and beyond - used magnetrons of about 55KW peak output. (The RDR- and some later RCA are X-band, 9.3 GHz.) That works out to about 750 watts average (heating) power - hmmm - the same as a full size microwave oven. The actual unsafe distance for personnel is a 15 foot arc in front of the radome. McDouglas used to have those areas painted in red on the concrete on the flight ramp where the new planes were parked.
Sometimes there would be rabbit tracks on the radar display in the days of old, from picking up another plane's radar. That was eliminated with the Arinc 700 generation by varying the pulses so the radar would track only its own.
With the 767 came Arinc 700 avionics, and the first new generation of Wx radars, the Collins WXR-700, and the Bendix RDR-4A. They had solid state transmitters of 60 to 150 watts peak power, for an average heating power of less than one watt. You will have to be close enough to get pranged in the head by the swinging antenna before you are harmed by that power level.
Why do these radar distance cautions still exist? Old beliefs and old airplanes die hard. There are still airliners flying with the old magnetron radars.
Meanwhile, your DMEs and maybe transponder and TCAS are probably transmitting continuously with up to 500 watts peak power. Ever see a precaution about being too close to their antennas?
GB
Still, a person calling himself engineer without specifying what type confuses me.
Oh, I'm sure most of the airlines have their radar antenna maintenance "on condition," rather than on "hard time." I knew one FAA Principal Avionics Inspector who required radar antenna overhaul at 9,000 hours, as he insisted, rightly, that mechanical parts wear out. Their MTBUR, Mean Time Between Unscheduled Removals, was much higher than other airlines as a result.
As for too many early radars in the area causing ATC radar problems: highly unlikely, as ATC radar has been S band, around 2 GHz, like your microwave oven, while the early RCA radars were C band, above 5 GHz. More likely, too many transponder replies were overloading ATC. That was one reason for the ALT OFF switch on the transponder control panel.
The RCA radars of the 1960s and 70s, AVQ-10 and AVQ-30 and the Bendix RDR-1E and RDR-1F of the same era - and beyond - used magnetrons of about 55KW peak output. (The RDR- and some later RCA are X-band, 9.3 GHz.) That works out to about 750 watts average (heating) power - hmmm - the same as a full size microwave oven. The actual unsafe distance for personnel is a 15 foot arc in front of the radome. McDouglas used to have those areas painted in red on the concrete on the flight ramp where the new planes were parked.
Sometimes there would be rabbit tracks on the radar display in the days of old, from picking up another plane's radar. That was eliminated with the Arinc 700 generation by varying the pulses so the radar would track only its own.
With the 767 came Arinc 700 avionics, and the first new generation of Wx radars, the Collins WXR-700, and the Bendix RDR-4A. They had solid state transmitters of 60 to 150 watts peak power, for an average heating power of less than one watt. You will have to be close enough to get pranged in the head by the swinging antenna before you are harmed by that power level.
Why do these radar distance cautions still exist? Old beliefs and old airplanes die hard. There are still airliners flying with the old magnetron radars.
Meanwhile, your DMEs and maybe transponder and TCAS are probably transmitting continuously with up to 500 watts peak power. Ever see a precaution about being too close to their antennas?
GB
Last edited by Graybeard; 29th Jan 2010 at 15:59. Reason: mispel
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Points well made Graybeard, names are confusing I guess, For a ‘box’ change, a technician (or in actual fact an airframe/engine Licensed Engineer) can issue a CRS. (Provided that no external test equipment is used, and the aircraft in question has a BITE Go/No Go system). As a scanner is technically an antenna only an Avionics Licensed Engineer may issue a CRS for a scanner change. Licensing here in the UK heavily splits into specialised Mechanical/Avionic disciplines, whereas the A&P is more general in it’s scope. (Don’t get me wrong, I know several A&P guys in JFK, a couple of which are among the best engineers I’ve ever known). The Mechanical licensed guy here will have limited avionics knowledge/certification powers.
Yep, the biggest danger from a modern radar is to be clocked in the head by the scanner.
I have to admit, I too have often wondered about the DME, Transponder and lower TCAS antennas radiating all this power downwards, onto baggage loaders, refuelers etc, no warning lables on these, and they’re powered all of the time.
Back to the radar switched off issue; on my previous high-flying aircraft, (cruise was betwwen 50 & 60,000'), we also tinkered with the idea of switching the radar to STBY during taxi. This was because the old AVQ-30 stabilisation was constantly fighting the nodding of the nose during taxi, causing premature failures of the antenna servo system and bearings.
Keep posting GB, you know your stuff.
Yep, the biggest danger from a modern radar is to be clocked in the head by the scanner.
I have to admit, I too have often wondered about the DME, Transponder and lower TCAS antennas radiating all this power downwards, onto baggage loaders, refuelers etc, no warning lables on these, and they’re powered all of the time.
Back to the radar switched off issue; on my previous high-flying aircraft, (cruise was betwwen 50 & 60,000'), we also tinkered with the idea of switching the radar to STBY during taxi. This was because the old AVQ-30 stabilisation was constantly fighting the nodding of the nose during taxi, causing premature failures of the antenna servo system and bearings.
Keep posting GB, you know your stuff.
Last edited by M2dude; 31st Jan 2010 at 00:20.
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With ADF etc and the likes generally we all have received 'training' in using the instrument, and interpreting its information, either as part of the ATPL syllabus or more likely to pass the IR test.
Also with the likes of other equipment eng-anti ice etc ..there are clear guidelines as to when its use is required and can be found in a variety of sources of manuals.
The main reason in the first place in posting these questions came about from trying to ‘teach’ or rather I should say ‘explain’ what I thought was a very ‘easy’ solution. But how do you start when there are no company SOP’s on its use, NO entry in the FCOM about even turning the thing on at all and a clearly general lack of understanding on how the damn thing works in the first place.
I have other sources to try and obtain a ‘definitive’ answer but as this post shows sometimes there is a lack of training and understanding in professional organisation relating to often held old beliefs.
When my own daughter ever asks a question Daddy Why is ....? to be honest sometimes the question is smarter than the answer but I always try and provide a correct answer rather than ‘Because that’s how it just is’.....
To date I have not yet found a definitive source that I can refer to ....to increase my own understanding of ‘how’ the system works and help others .
Maybe I should have been an engineer instead....lol
My thanks to all so far.......keep it coming......
Also with the likes of other equipment eng-anti ice etc ..there are clear guidelines as to when its use is required and can be found in a variety of sources of manuals.
The main reason in the first place in posting these questions came about from trying to ‘teach’ or rather I should say ‘explain’ what I thought was a very ‘easy’ solution. But how do you start when there are no company SOP’s on its use, NO entry in the FCOM about even turning the thing on at all and a clearly general lack of understanding on how the damn thing works in the first place.
I have other sources to try and obtain a ‘definitive’ answer but as this post shows sometimes there is a lack of training and understanding in professional organisation relating to often held old beliefs.
When my own daughter ever asks a question Daddy Why is ....? to be honest sometimes the question is smarter than the answer but I always try and provide a correct answer rather than ‘Because that’s how it just is’.....
To date I have not yet found a definitive source that I can refer to ....to increase my own understanding of ‘how’ the system works and help others .
Maybe I should have been an engineer instead....lol
My thanks to all so far.......keep it coming......
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BGA you are so welcome. The beauty of a forum such as this, is that fellow professionals can help each other's understanding of such an amazing subject - Aviation
(Digging up some info regarding REACTIVE windshear detection within the EGPWC.. Mode 7.. We obviously are looking for a sudden increase in IAS without a corresponding increase in Longditudinal Acceleration at trigger altitude etc conditions, but there is more to Mode 7 than just this; Watch this space). Although by definition Reactive Windshear detection means that you are already 'in it' (the microburst downdraft spread) it is the very early stages of the windshear, and hopefully applying the correct 'escape procedure' gives the pilot a fighting chance to get out of it.
(Digging up some info regarding REACTIVE windshear detection within the EGPWC.. Mode 7.. We obviously are looking for a sudden increase in IAS without a corresponding increase in Longditudinal Acceleration at trigger altitude etc conditions, but there is more to Mode 7 than just this; Watch this space). Although by definition Reactive Windshear detection means that you are already 'in it' (the microburst downdraft spread) it is the very early stages of the windshear, and hopefully applying the correct 'escape procedure' gives the pilot a fighting chance to get out of it.
Last edited by M2dude; 30th Jan 2010 at 21:34. Reason: Too quick, I forgot. Sign of Age.
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I Had a Dream..
If I were a dreamer, I would look forward to mandatory thorough Wx radar training for all airline pilots as one of the results of the loss of AF-447. I would also expect the requirement for workload reducing multi-scan radar, if not by regulation, then by pilot association bargaining.
GB
GB