Some Airbus questions...
leewan;
I recall a medical diversion into Anchorage - overweight landing, very high approach speeds - if I recall, we heated the brakes to well over 600C. Alaskan Airlines put eight coolers on the mains while we refueled; we turned in 26 minutes and left with brakes under around 100C, so coolers work well. Airbus recommends releasing the brakes when they're over 300C, again going by memory.
Boeing has a different philosophy (which some airlines have adopted). "Unless the pilot reports it, it didn't happen".
That applies to hard landings, high brake temps, CAT and anything else that could be considered an operational matter. If it isn't in the log book, it didn't occur. So, if we see a landing in the data which exceeds the Aircraft Maintenance Manual limits, (higher than 1.9g's with a roll angle greater than 5deg at touchdown) and it is not reported by the pilot, it "didn't happen", and the aircraft continues to fly.
The B777 brake temps are indicated on a scale from 1-10 on the EICAS; the AMM (Aircraft Maintenance Manual) refers to a substantially different scale and I can't find a conversion for the readings. It appears as though anything over a "5" requires cooling - actual brake temps aren't displayed.
Airbus treats these kinds of issues quite differently.
I recall a medical diversion into Anchorage - overweight landing, very high approach speeds - if I recall, we heated the brakes to well over 600C. Alaskan Airlines put eight coolers on the mains while we refueled; we turned in 26 minutes and left with brakes under around 100C, so coolers work well. Airbus recommends releasing the brakes when they're over 300C, again going by memory.
Boeing has a different philosophy (which some airlines have adopted). "Unless the pilot reports it, it didn't happen".
That applies to hard landings, high brake temps, CAT and anything else that could be considered an operational matter. If it isn't in the log book, it didn't occur. So, if we see a landing in the data which exceeds the Aircraft Maintenance Manual limits, (higher than 1.9g's with a roll angle greater than 5deg at touchdown) and it is not reported by the pilot, it "didn't happen", and the aircraft continues to fly.
The B777 brake temps are indicated on a scale from 1-10 on the EICAS; the AMM (Aircraft Maintenance Manual) refers to a substantially different scale and I can't find a conversion for the readings. It appears as though anything over a "5" requires cooling - actual brake temps aren't displayed.
Airbus treats these kinds of issues quite differently.
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Thanks for the info, PJ2. Just wondering, what bus were u flying then ?
The B777 brake temp is indicated by values ranging 0.0 to 9.9 If the value is white, then it's normal. If it's amber( > 5.0), it's hot. As PJ2 mentioned, Boeing takes a pilot knows best philosophy when designing their a/c. Airbus a/c let everyone knows every single problem it has. For ex: If you oversteer an airbus during pushback or towing, an oversteer warning light will light up in the cockpit. For the Boeing, no such warning unless if the ground staff brings it up.
The B777 brake temp is indicated by values ranging 0.0 to 9.9 If the value is white, then it's normal. If it's amber( > 5.0), it's hot. As PJ2 mentioned, Boeing takes a pilot knows best philosophy when designing their a/c. Airbus a/c let everyone knows every single problem it has. For ex: If you oversteer an airbus during pushback or towing, an oversteer warning light will light up in the cockpit. For the Boeing, no such warning unless if the ground staff brings it up.
The diversion into Anchorage was in an A340-300 - approach speed about 160kts or so.
Both manufacturer's philosophies seem to work except where a FOQA program is involved. Then, to me anyway, if we know that an aircraft has exceeded the manufacturer's limits as set out in the AMM but the pilot hasn't logged the event, then how can flight operations or maintenance say "it didn't happen" when the data shows it did? To me that opens a huge liability issue but there it is, we've tried to get answers but we're greeted with silence.
As far as philosophies go, I prefer knowing to not knowing, and that includes what the aircraft has been through. If it's had a hard landing and it isn't reported by the crew that did it, there is a problem and it's more than an ethical one, it's a safety problem. That said, Boeing is clear and so is the airline's flight ops and maintenance departments: if the pilot didn't report it, it didn't happen.
On that basis, regardless of what it says, the FOQA data is dismissed, outright, I am informed.
Also, as far as I know, its still not an issue if a crew decides to take off with the brake temps higher than 300C. No directives and no communications with the pilots have said otherwise and the few times it has happened, it has been excused as "special circumstances" by management personnel.
Both manufacturer's philosophies seem to work except where a FOQA program is involved. Then, to me anyway, if we know that an aircraft has exceeded the manufacturer's limits as set out in the AMM but the pilot hasn't logged the event, then how can flight operations or maintenance say "it didn't happen" when the data shows it did? To me that opens a huge liability issue but there it is, we've tried to get answers but we're greeted with silence.
As far as philosophies go, I prefer knowing to not knowing, and that includes what the aircraft has been through. If it's had a hard landing and it isn't reported by the crew that did it, there is a problem and it's more than an ethical one, it's a safety problem. That said, Boeing is clear and so is the airline's flight ops and maintenance departments: if the pilot didn't report it, it didn't happen.
On that basis, regardless of what it says, the FOQA data is dismissed, outright, I am informed.
Also, as far as I know, its still not an issue if a crew decides to take off with the brake temps higher than 300C. No directives and no communications with the pilots have said otherwise and the few times it has happened, it has been excused as "special circumstances" by management personnel.
