Pratt & Whitney Les nouveaux GTF "Purepower"

Paul a écrit:Comparaison sonore au décollage entre un A320-211 (CFM56) vs A320-271 (PW1100G-JM)

Pratt & Whitney has confirmed that the first engines incorporating hardware modifications to speed up the start time of the PW1100G geared turbofan have shipped to Airbus for installation on the A320neo.

Slower starting allows more even heating, which eliminates differential thermal deformation. Engine-control software, introduced as an interim measure, interrupts the start sequence at 10% N2 (low-pressure spool speed). The pilots’ central display informs them that the respective engine is “cooling.” Once sensors inside the engine signal that the process has minimized the temperature differences to acceptable levels, normal start-up resumes.

Pratt is delivering revisions that will take the maximum cooling time down to 90 seconds in June and, combined with the latest hardware fixes, will subsequently bring start times in line with the V2500. The upgrade package includes revised tips on the eighth stage of the high-pressure compressor. Introduced into the production process in February, the change adds a toughened coating of cubic boron nitride (CBN) to the tips of the integrally bladed rotor (IBR). The PW1100G’s eight HP compressor stages and three low-pressure (LP) compressor stages are all IBRs.

UTC CFO says GTF production run-rate in Q4 & Jan encouraging. Sticks with 2017 delivery plans of 350-400 engines https://t.co/0DMxT3ENiq

— Robert Wall (@R_Wall) 25 janvier 2017

Frequent Traveller a écrit:350-400 unités GTF ... mais est-ce suffisant ? Car ça veut dire qu'on equipera 175 - 200 cellules d'avion, qui elles se produisent au rythme de ... ? 52 par mois, tendant vers les 60 seulement chez Airbus.