Have a question regarding CFRI charts. I'm coming back from a LOA and transitioning onto the Airbus for the first time and just looking through the manuals
Do you first start on the Landing Distance Without Autobrake config full (4.30), determine the actual landing distance then transition to the CRFI chart No Reverse. Then move along on the column 60% Factor till the corresponding CFRI for the runway.
Too long in the dunes
CFRI cahrts
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the dude67
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Re: CFRI cahrts
You never use the factored CRFI chart because that is for dispatch only. In-flight you would use the autoland landing distance with autobrake and use either the CRFI chart (unfactored) or the contamination numbers out of the same chart. That will give you real world performance.
Required landing distance is a different animal and is Airbus saying "Our test pilots using perfect technique, crossing the threshold at 50' and VREF, and touching down with minimal flare and maximum braking can get the aircraft stopped in XXXX ft." This has little resemblance to real life, but when you calculate required landing distance for TC purposes that's what you use. They are the landing distance without autobrake config full or config 3 tables. If you have an abnormal you add the landing distance factor to landing distance without autobrake config full.
If you are transitioning to the bus for the first time it is just one of the things that will confuse the hell out of you for the first little while. Best to wait until ground school when you can go over this stuff with an instructor and the QRH in hand.
Required landing distance is a different animal and is Airbus saying "Our test pilots using perfect technique, crossing the threshold at 50' and VREF, and touching down with minimal flare and maximum braking can get the aircraft stopped in XXXX ft." This has little resemblance to real life, but when you calculate required landing distance for TC purposes that's what you use. They are the landing distance without autobrake config full or config 3 tables. If you have an abnormal you add the landing distance factor to landing distance without autobrake config full.
If you are transitioning to the bus for the first time it is just one of the things that will confuse the hell out of you for the first little while. Best to wait until ground school when you can go over this stuff with an instructor and the QRH in hand.
Re: CFRI cahrts
Rockie,
I believe most transport catagory aircraft manufacturers data is based on average pilot skill and average airframe life.
I believe most transport catagory aircraft manufacturers data is based on average pilot skill and average airframe life.
Re: CFRI cahrts
I was always told performance data was based on actual test pilot findings conducted on new airframes under regulators specified controlled conditions. It would be surprising if the manufactures or regulators dumbed down the results. However AC does correct the fuel burn for individual airframes during their service life as performance does vary with age.Bede wrote:Rockie,
I believe most transport catagory aircraft manufacturers data is based on average pilot skill and average airframe life.
Re: CFRI cahrts
Not in this case. In the airbus we have to determine the required landing distance in the case of an abnormal, and that is using the tables that I mentioned which are based on the performance that I mentioned. If you want to know what real life is like you use the autoland with autobrake table which is more representative of an actual landing.Bede wrote:Rockie,
I believe most transport catagory aircraft manufacturers data is based on average pilot skill and average airframe life.
Hey, I didn't build it or come up with the requirement. That's just the way it is with this airplane.
Re: CFRI cahrts
I thought I would post this from the horse's mouth. Airbus publishes an excellent series called "Coming to Grips with..." covering a very wide array of topics, one of which is performance that I've taken the following quote from. The series is widely available on the web and I would strongly recommend them to anybody flying a new generation Airbus.
3.2. Actual Landing Distance (ALD)
JAR 25.125 Subpart B FAR 25.125 Subpart B
3.2.1. Manual Landing
“JAR/FAR 25.125
(a)The horizontal distance necessary to land and to come to a complete stop from a point 50 ft above the landing surface must be determined (for standard temperatures, at each weight, altitude and wind within the operational limits established by the applicant for the aeroplane) as follows:
• The aeroplane must be in the landing configuration
• A stabilized approach, with a calibrated airspeed of VLS must be maintained down to the 50 ft.”
During airplane certification, the actual landing distance is demonstrated as
follows:
It is the distance measured between a point 50 feet above the runway threshold, and the point where the aircraft comes to a complete stop. To determine this actual landing distance, several conditions must be achieved:
• Standard temperature
• Landing configuration
• Stabilized approach at VLS (or VMCL whichever is greater) for the configuration for manual landing.
• Non excessive vertical acceleration
• Determination on a level, smooth, dry, hard-surfaced runway
• Acceptable pressures on the wheel braking systems
• Braking Means other than wheel brakes: Spoilers, reversers (except on dry runway), can be used when they are safe and reliable.
Actual landing distance is also certified with degraded braking means (spoiler inoperative, one brake inoperative…).
Actual Landing Distances are certified on dry runways for all Airbus aircraft, certified on contaminated and icy runways for all fly-by-wire aircraft and published (for information) for wet.
Demonstrated landing distances will not account for reversers on dry runways. The reverse thrust influence may be considered on contaminated runways.
On dry runways, landing distances are demonstrated with standard temperatures, according to JAR/FAR 25. However, on contaminated runways, Airbus decided to take into account the influence of temperature on landing distance demonstration. This choice ensures added safety as it gives a conservative ALD.
Landing distance data must include correction factors for no more than 50% of the nominal wind components along the landing path opposite to the landing direction, and no less than 150% of the nominal wind components along the landing path in the landing direction. This is already taken into account in published figures and corrections.
3.2. Actual Landing Distance (ALD)
JAR 25.125 Subpart B FAR 25.125 Subpart B
3.2.1. Manual Landing
“JAR/FAR 25.125
(a)The horizontal distance necessary to land and to come to a complete stop from a point 50 ft above the landing surface must be determined (for standard temperatures, at each weight, altitude and wind within the operational limits established by the applicant for the aeroplane) as follows:
• The aeroplane must be in the landing configuration
• A stabilized approach, with a calibrated airspeed of VLS must be maintained down to the 50 ft.”
During airplane certification, the actual landing distance is demonstrated as
follows:
It is the distance measured between a point 50 feet above the runway threshold, and the point where the aircraft comes to a complete stop. To determine this actual landing distance, several conditions must be achieved:
• Standard temperature
• Landing configuration
• Stabilized approach at VLS (or VMCL whichever is greater) for the configuration for manual landing.
• Non excessive vertical acceleration
• Determination on a level, smooth, dry, hard-surfaced runway
• Acceptable pressures on the wheel braking systems
• Braking Means other than wheel brakes: Spoilers, reversers (except on dry runway), can be used when they are safe and reliable.
Actual landing distance is also certified with degraded braking means (spoiler inoperative, one brake inoperative…).
Actual Landing Distances are certified on dry runways for all Airbus aircraft, certified on contaminated and icy runways for all fly-by-wire aircraft and published (for information) for wet.
Demonstrated landing distances will not account for reversers on dry runways. The reverse thrust influence may be considered on contaminated runways.
On dry runways, landing distances are demonstrated with standard temperatures, according to JAR/FAR 25. However, on contaminated runways, Airbus decided to take into account the influence of temperature on landing distance demonstration. This choice ensures added safety as it gives a conservative ALD.
Landing distance data must include correction factors for no more than 50% of the nominal wind components along the landing path opposite to the landing direction, and no less than 150% of the nominal wind components along the landing path in the landing direction. This is already taken into account in published figures and corrections.
