less noise with 4 degrees glideslope
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thermostat,
2.8 degrees too flat, that is crap...
note that criteria max GPA for CAT C is 3.6 and CAT D is 3.1 degrees MAX!
For CAT D, we use 2.8 as the standard...
With baro-vnav, the min effective GPA is 2.5. That drives where you see the NA below temp, with 3.1 driving the NA above temp.
MLS never took off because the accuracy of the typical system is not much better than GPS. Heathrow has a custom system, and is used instead of the ILS in low vis situations...but its still DME/Precision.
The US no longer has any MLS procedures on the books...
2.8 degrees too flat, that is crap...
note that criteria max GPA for CAT C is 3.6 and CAT D is 3.1 degrees MAX!
For CAT D, we use 2.8 as the standard...
With baro-vnav, the min effective GPA is 2.5. That drives where you see the NA below temp, with 3.1 driving the NA above temp.
MLS never took off because the accuracy of the typical system is not much better than GPS. Heathrow has a custom system, and is used instead of the ILS in low vis situations...but its still DME/Precision.
The US no longer has any MLS procedures on the books...
Last edited by FlightPathOBN; 15th Sep 2012 at 19:35.
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LCY runway
The article about the Airbus 318 landing at LCY gives the runway length at LCY as 1199 metres/3650 feet which are very precise figures obviously quoted from somewhere. According to the UK AIP chart it is 1508 metres/4947 feet. Have I missed something?
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LCY runway
SP Many thanks. So its the difference between TORA and actual runway length. I've been out of the loop for 13 years, can't remember all the abbreviations.
The writer did say runway length.
The writer did say runway length.
Last edited by Boslandew; 16th Sep 2012 at 08:05.
MLS works fine in rain.
The FAA favoured GPS only after fighting for world leadership of the MLS design with an inferior system, then discovering that the costs of re-equipping was not justified by their requirement for Cat 3. Thus the already funded GPS was selected as being capable of achieving Cat 3 integrity in the future at lower cost.
MLS was demonstrated at 1 deg glidepath showing interference free operation, and for potential military / helicopter applications.
The LCY runway was initially limited to 1199m to comply with the ICAO code 2 runway requirements (1200m limit). This provided the necessary lateral obstacle free zones and distances to the water hazards in the event of lateral or longitudinal runway excursion. With evolving common sense it has been possible to lengthen some aspects the runway whilst maintaining obstacle clearance (height of parked aircraft tails) and providing alternative overrun protection.
Runway extension to the West is not easy due to the (real) approach obstacles, but to the East with the absence of the mythical East London River Crossing Bridge the approach could be adjusted. The 5.5deg slope is retained for noise reasons.
The FAA favoured GPS only after fighting for world leadership of the MLS design with an inferior system, then discovering that the costs of re-equipping was not justified by their requirement for Cat 3. Thus the already funded GPS was selected as being capable of achieving Cat 3 integrity in the future at lower cost.
MLS was demonstrated at 1 deg glidepath showing interference free operation, and for potential military / helicopter applications.
The LCY runway was initially limited to 1199m to comply with the ICAO code 2 runway requirements (1200m limit). This provided the necessary lateral obstacle free zones and distances to the water hazards in the event of lateral or longitudinal runway excursion. With evolving common sense it has been possible to lengthen some aspects the runway whilst maintaining obstacle clearance (height of parked aircraft tails) and providing alternative overrun protection.
Runway extension to the West is not easy due to the (real) approach obstacles, but to the East with the absence of the mythical East London River Crossing Bridge the approach could be adjusted. The 5.5deg slope is retained for noise reasons.
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safety pee:
All I know about FAA MLS in the mid-1970s was the airlines wouldn't touch it. They had just spent a bundle on fail-active autholand tied to high-quality ILSes.
GPS can do great curved paths although I am not sure where those would be required at the major airports that have CAT III, at least in the U.S.
MLS works fine in rain.
The FAA favoured GPS only after fighting for world leadership of the MLS design with an inferior system, then discovering that the costs of re-equipping was not justified by their requirement for Cat 3. Thus the already funded GPS was selected as being capable of achieving Cat 3 integrity in the future at lower cost.
The FAA favoured GPS only after fighting for world leadership of the MLS design with an inferior system, then discovering that the costs of re-equipping was not justified by their requirement for Cat 3. Thus the already funded GPS was selected as being capable of achieving Cat 3 integrity in the future at lower cost.
GPS can do great curved paths although I am not sure where those would be required at the major airports that have CAT III, at least in the U.S.
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Glide Slope
Attack, attack, attack. Seems that some PPruners are only happy when on the defensive. Too bad we can't discuss items without the attacks.
Cough : That was my understanding when they were trying to develop the MLS system many years ago.
FlightpathOBN : Don't shoot the messenger. I am quoting from the Airbus CFIT manual. Due to many landing accidents in the past, research shows the 3 to 3.7 degree slope to be the best angles for large jet transport. That does not mean that some chart producers won't produce charts with less than 3 degrees. It's just not as safe as the larger angles, obviously. Airbus spent millions of $$ to develop the FPA system which I thought was the best invention in years. Instead of dragging the aircraft in on final with high power at 2.8 deg, why not fly down the slope at a more comfortable 3 deg. with more clearance from obstacles? Safety first.
I don't understand your bravo-nav statement. Please explain.
Why does the USA no longer have a MLS system? Again please explain.
Safetypee. What type of aircraft uses the 5.5 deg slope ?
AND PLEASE, NO MORE ATTACKS !!!!!!!!!!!!!!!!!!!!!!!!!!
Cough : That was my understanding when they were trying to develop the MLS system many years ago.
FlightpathOBN : Don't shoot the messenger. I am quoting from the Airbus CFIT manual. Due to many landing accidents in the past, research shows the 3 to 3.7 degree slope to be the best angles for large jet transport. That does not mean that some chart producers won't produce charts with less than 3 degrees. It's just not as safe as the larger angles, obviously. Airbus spent millions of $$ to develop the FPA system which I thought was the best invention in years. Instead of dragging the aircraft in on final with high power at 2.8 deg, why not fly down the slope at a more comfortable 3 deg. with more clearance from obstacles? Safety first.
I don't understand your bravo-nav statement. Please explain.
Why does the USA no longer have a MLS system? Again please explain.
Safetypee. What type of aircraft uses the 5.5 deg slope ?
AND PLEASE, NO MORE ATTACKS !!!!!!!!!!!!!!!!!!!!!!!!!!
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BN2A:
Next to the Concorde the "water wagon" version of the 707 would bring tears to your eyes as your ears shut down.
Bring back Concorde, the VC10, the 707, the Trident, etc etc etc....
Creates a bit of perspective!!
Creates a bit of perspective!!
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I think its time to show the kids what a REAL jet sounded like back in the
days when we flew 'em. Ensure yer speakers/headset are up full blast.......
Ah that JT8D grunt - still brings a tear to me eye!
days when we flew 'em. Ensure yer speakers/headset are up full blast.......
Ah that JT8D grunt - still brings a tear to me eye!
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thermostat,
Are you a pilot?
I am not sure what about baro-vnav you dont understand.
The reason why the US doesnt use MLS was already answered by several posters.
Are you a pilot?
I am not sure what about baro-vnav you dont understand.
The reason why the US doesnt use MLS was already answered by several posters.
MLS – the original concept of MLS was as the ICAO standard approach aid to replace ILS.
In the late 1970s ILS was projected to suffer co-channel interference problems with a rapidly expanding industry. Most Cat 1 operations could tolerate some interference, but for Cat 2 and particularly Cat 3 this was seen as a major safety issue for autocoupled approaches.
History shows otherwise, with a less than anticipated runway expansion, and lower Cat 3 demand, also that modern ILS / auto flight systems and careful ILS location reduces the problem.
The US won the MLS competition for the system design (time ref scanning beam) which like other systems could offer area navigation type approaches, but the straight-in ILS replacement was the priority, and this, particularly for Cat 1 and the urgent safety upgrade of NPAs to ILS, could be met by the emerging GPS with FMS R Nav.
The FAA quietly dropped MLS in favour of GPS, leaving Europe to solve the higher integrity problems for Cat 3 ILS. Some US views will claim GPS capable Cat 3, but perhaps the integrity is not yet as that required in Europe.
What type of aircraft uses the 5.5 deg slope ?
Some time since I visited LCY:-
Originally Dash 7 at 7.5 deg, then BAe146 / Avro RJ (all variants) at 5.5 deg.
Fokker tried the F70 (not very successfully ?), Saab 340, and other turboprops … ???
Airbus 318, and several Biz Jet types … .
Flight Path Angle (FPA) is a useful instrument aid, but its use during approach and landing requires knowledge of where the intended point of touchdown is.
Hence some of the first applications were displays on HUD where the FPA could be overlaid on the runway – but this also required a marker which designated the required flight path angle, so that when all were coincident the aircraft was on the correct approach path.
The similar head-down application requires an electronic (ground referenced) glideslope to determine the point of landing, hence use of FPA as/with a FD.
In the late 1970s ILS was projected to suffer co-channel interference problems with a rapidly expanding industry. Most Cat 1 operations could tolerate some interference, but for Cat 2 and particularly Cat 3 this was seen as a major safety issue for autocoupled approaches.
History shows otherwise, with a less than anticipated runway expansion, and lower Cat 3 demand, also that modern ILS / auto flight systems and careful ILS location reduces the problem.
The US won the MLS competition for the system design (time ref scanning beam) which like other systems could offer area navigation type approaches, but the straight-in ILS replacement was the priority, and this, particularly for Cat 1 and the urgent safety upgrade of NPAs to ILS, could be met by the emerging GPS with FMS R Nav.
The FAA quietly dropped MLS in favour of GPS, leaving Europe to solve the higher integrity problems for Cat 3 ILS. Some US views will claim GPS capable Cat 3, but perhaps the integrity is not yet as that required in Europe.
What type of aircraft uses the 5.5 deg slope ?
Some time since I visited LCY:-
Originally Dash 7 at 7.5 deg, then BAe146 / Avro RJ (all variants) at 5.5 deg.
Fokker tried the F70 (not very successfully ?), Saab 340, and other turboprops … ???
Airbus 318, and several Biz Jet types … .
Flight Path Angle (FPA) is a useful instrument aid, but its use during approach and landing requires knowledge of where the intended point of touchdown is.
Hence some of the first applications were displays on HUD where the FPA could be overlaid on the runway – but this also required a marker which designated the required flight path angle, so that when all were coincident the aircraft was on the correct approach path.
The similar head-down application requires an electronic (ground referenced) glideslope to determine the point of landing, hence use of FPA as/with a FD.
What type of aircraft uses the 5.5 deg slope ?
Some time since I
visited LCY:-
Originally Dash 7 at 7.5 deg, then BAe146 / Avro RJ (all
variants) at 5.5 deg.
Fokker tried the F70 (not very successfully ?), Saab
340, and other turboprops … ???
Airbus 318, and several Biz Jet types …
Some time since I
visited LCY:-
Originally Dash 7 at 7.5 deg, then BAe146 / Avro RJ (all
variants) at 5.5 deg.
Fokker tried the F70 (not very successfully ?), Saab
340, and other turboprops … ???
Airbus 318, and several Biz Jet types …
