FMS Cruise Altitudes Danilo Mayer Embraer Services & Support This information is property of Embraer and cannot be used or reproduced without written permission. This information is property of Embraer and cannot be used or reproduced without written permission. Ceiling Altitude Structure Maximum differential pressure (FL410) Aerodynamic Buffet limits (1.3 g) for maneuvers and turbulence Engine Maximum thrust to overcome drag Residual Climbing capability This information is property of Embraer and cannot be used or reproduced without written permission. Ceiling altitude Ceiling altitude OFP FMS ceiling altitude is based on tables Generated with Embraer Inflight Performance Software Same source for AOM and Operational Flight Plan Residual ROC 300 ft/min CLB thrust mode This information is property of Embraer and cannot be used or reproduced without written permission. Load 25 Flying above ceiling Load 25 PERF DATA does not match the actual flight level This information is property of Embraer and cannot be used or reproduced without written permission. Residual ROC lower than 300 ft/min Ceiling altitude OFP FMS ceiling altitude based on airplane/engine raw data Inflight Software and FMS with similar calculation module Residual ROC customizable Default 300 ft/min APM settings This information is property of Embraer and cannot be used or reproduced without written permission. Load 27 Residual Rate of Climb FMS ceiling RROC @ CRZ thrust mode RROC @ CRZ thrust mode CLB thrust mode Default settings 300 ft/min This information is property of Embraer and cannot be used or reproduced without written permission. Load 27 Residual Rate of Climb AOM/OFP ceiling FMS ceiling RROC @ CRZ thrust mode RROC @ CRZ thrust mode CLB thrust mode Default settings 300 ft/min This information is property of Embraer and cannot be used or reproduced without written permission. Load 27 RROC @ CLB thrust mode RROC @ CLB thrust mode Flying above ceiling Load 27 PERF DATA matches the actual flight level This information is property of Embraer and cannot be used or reproduced without written permission. Residual ROC lower than APM setting Ceiling fluctuations at low temperature Engine raw data No data for ISA-15 (outside envelope) For interpolation, FMS considers ceiling altitude null at ISA-15 New FMS AEDB required E170/175 Load 27 This information is property of Embraer and cannot be used or reproduced without written permission. Reports: Fluctuations and sudden drop of ceiling altitude This information is property of Embraer and cannot be used or reproduced without written permission. Optimum Altitude FMS Optimum altitude maximizes Cruise SPECIFIC RANGE (NM/kg) Specific Range (NM/Kg) This information is property of Embraer and cannot be used or reproduced without written permission. Altitude that minimizes fuel for the entire route Altitude (ft) Optimum Altitude Load 25 Load 27 Optimum altitude is the default cruise altitude No default Default cruise altitude labeled (OPTIMUM) Cruise altitude inserted by flight crew This information is property of Embraer and cannot be used or reproduced without written permission. Default cruise altitude Load 25 Load 27 Short trip ― Cruise altitude adjusted No default Default cruise altitude is displayed and labeled (FP LIM) Actual OPT altitude is not affected Still based on maximum specific range Cruise altitude inserted by flight crew This information is property of Embraer and cannot be used or reproduced without written permission. Altitude limited by Flight Plan Optimum Altitude Load 25 EMBRAER 195 M0.78 41000 40000 39000 Altitude (ft) 38000 FMS 37000 Inflight Software 36000 35000 34000 33000 32000 31000 30000 0.19 0.21 0.23 0.25 0.27 Specific Range (NM/Kg) 0.29 0.31 This information is property of Embraer and cannot be used or reproduced without written permission. Table interpolation Optimum Altitude Load 25 FADEC controls engine thrust electronically FMS optimum altitude calculation may not result in the maximum SR EMBRAER 190 LONG RANG CRUISE Altitude (ft) 41000 39000 37000 35000 33000 31000 0.19 0.21 0.23 0.25 0.27 Specific Range (NM/Kg) 0.29 0.31 0.33 This information is property of Embraer and cannot be used or reproduced without written permission. As a consequence, actual data does not always match the theory This information is property of Embraer and cannot be used or reproduced without written permission. Optimum Altitude Load 27 Load 25 Load 27 FMS Ceiling matches AOM and OFP FMS Ceiling residual ROC based on CRZ thrust mode Fixed residual ROC 300 ft/min FMS Optimum affected by interpolation and engine control AOM and OFP based on CLB thrust mode Residual ROC customizable FMS Optimum based on single point calculation This information is property of Embraer and cannot be used or reproduced without written permission. FMS cruise altitudes ― Summary embraer.com
