MD-80 parte 7 – Schemi tecnici 6 – Engines

Engines: 2 * turbo fan / flat rated 28.9 C 84 F / No der. < 38 C Min pneum. press 36 Psi / 1000 FT PA < 1 Psi ok Oil quan. 12-16 qua Oil press norm. 40-55 psi Oil temp. norm. 135 C Oil temp. max 5 min 163 C Max EGT 475 C (ON GROUND) Max EGT 625 C (IN FLIGHT/Max T/O 5 Min) Max EGT MCT 580 Max EGT Idle Power 480 C Idle 300 - 480 C N2 50 - 61 % Idle Fuel Flow 270 - 500 kg/h During Start 500 Kg Fuel flow (HOT START) Remark Good Proc. for Start: 30% N2, EGT may not increase 300 C Best fuel consumption, CG of 19% Fan 45% komp. 55% thrust Every engine, 2 fuel pumps 1 Stage Centrifugal Pump (Low) 2 Stage High Press. Gear Pump Pressure up 50 Psi with closed X Feed Valve Lever is in limits N1, low pressure N2, high pressure N2 Indicator u/s. Start at 5% N1 fuel lever on, starter release 12-20% N1. If EGT does not rise after 20 sec., abort engine start Startpwr. 20 Joule AC Cycle System A/B 10 Min ON, 10 Min Off Starter Duty Cycle 90 Sec ON, 5 Min OFF, 30 Sec ON, 5 Min OFF. Cont. Ignation Override Max 2 Min, 3 Min OFF, 2 Min, 3 Min OFF When engine stabilized below 50% N2, increase thrust 65% N2, 13 th "Stage Bleed Valve" will close Ignation A/B engine anti ice on between -10 C --- +6 C Fuel Heat ON is during T/O, APP, LDG and GA prohibited. C/L T/O Mode TRI computer stops changing EPR at 60 Kt TRI range 1-59 C Flex T/O: After engines start moving flaps/slats handle in position Master Caution comes on: Reason , ART is in OFF Position, ART Inop Light comes on Fire Warnings Engines: When fire handle is pulled, left or right, Aural Warning, Generator (GCR), Fuel, Hydraulic, Pneumatic Cross feed (Valve) will be closed Reset generators after you have pushed in fire handles In flight: Master Caution and Fire Detection Loop Light (Annunciator Panel) illuminated Quick RHB, TAB 23 ENG/APU FIRE DETECTOR LOOP LIGHT AND LOOP A OR B LIGHT ON WITHOUT FIRE WARNING...point "TEST INDICATIONS OBSERVE" Following indications are mandatory: 1. Fire Handle Light 2. Aural Warning 3. Fire detection Loop Light (Annunciator Panel) 4. Master Caution 5. Loop Lights (3*) (Overhead Panel) If all indications are observed, the test is "Satisfactory", further Quick RHB. If one does not come on, the test is "Unsatisfactory", further Quick RHB. When you select the other system (A/B) no visual or acoustic warning has to come on. Otherwise the test failed ART is fired by DFGS ART (Automatic Reserve Thrust): Will be actuated by Engine Failure Additional pwr (700 Pounds) ART on ground ready when switch auto, slats extend, both engines idle, Self test OK ART is armed when both engines has 64% RPM Additional pwr will come on if both N1 has a difference of 30,2% or not valid N1 or elo pwr loss or DFGS switching manual ATR (Automatic Thrust Restoration): At 60 Kt no Clmb, if auto throttle on EPR up to GA EPR ATR armed if flight director pitch axis is in T/O mode Aircraft is above 350 ft radio altitude Both engine EPR's are below GA EPR Limit Diff. 0.25 EPR = 7% N1. If vertical speed >5 Sec <0 F/Min

Dry Idle
Wet 1.3 EPR
Emerg. MAX EPR
Reverse reaction 2 Sec (Hydraulic)

Battery Start with External Air Supply: Ignation system is supplied by 115 Volt
AC Emergency Inverter

Engine BTTR Start:
Anti Collision Light ON
Emergency Power ON
Pneum. Press Gage CHECK
DC Start Pump ON
Engine Ignation A/B
Right Engine Start
Emergency Switch OFF
DC Start Pump OFF

Pneumatic Start:

Air cond. shut off switch OVERRIDE
Throttle right engine MIN 36 Psi / 1.25 EPR
Start switch release 22% engine oper.
Reduce to idle
Air cond. shut off switch AUTO

ART, Automatic Reserve Thrust


AC min. 20 sek. on ground
ART switch in auto
engines operating near idle
slats extended
ART self test completed

System is armed when both engines have more then 64% N1

ART actuates
DFGS detects, any one of

30,2 % diff. in N1

Invalid N1
DFGS failure
electrical power loss
manual DFGS switching


– ART increases EPR of operating engine from normal T/O to max T/O by opening fuel valve in FCU

ca. 0,05 EPR more


max T/O EPR is displayed in TRI and bug

ATR, Automatic Thrust Restoration

Derated T/O, engine failure or power cut back ATR restores max in-flight T/O thrust (is GA power) in good engine

System is armed when
FD pitch in T/O mode
AC is above 350 feet RA
both engines below GA limit

System activates

Diff. between engines more 0,25 EPR and
7% N1
AC descending for 5 sec.

Action – ATR unclamps throttles (if ATS is engaged)
– moves both trottles forward until one engine is on EPR limit

ATR unclamps throttles (if ATS is engaged)
moves both throttles until one engine is on EPR limit


if ART is armed and ATR is activated
EPR limit is max in flight T/O rating, less the increment of increase in thrust that ART is designed to provide