EFFECTIVITY:
040-999
Jan 10/9032-30-00
PIPERAIRCRAFT
PA-42-720(AdvancedTrainer)
MAINTENANCEMANUAL
A. ExtensionandRetraction(continued)
2. FaultIsolation-ExtensionandRetraction(continued)
CHART 1
FAULTISOLATION(EXTENSIONANDRETRACTION)(Sheet2 of 2)
Fault Cause Remedy
Maingearfailsto lock Uplockrodoutofadjustment. Adjustrod.
up.
Actuatoroutofadjustment. Adjustactuator.
Nogreenlightonpanel whengearsaredown. Lockswitchdefective oroutofadjustment. Replaceand/oradjust lockswitch.
Gearnotlockedindown Adjustthe gear. (referto
position. 32-10-00and32-20-00)
EFFECTIVITY:
040-999 PAGE 5
32-30-00Jan
Jan10/90
PIPERAIRCRAFT
PA-42-720(Advanced Trainer)
MAINTENANCEMANUAL
A. ExtensionandRetraction(continued)
3. ServicingAfter Activationof EmergencyGearExtensionSystem(EES) (referto 32-30-00 Figure 301)
NOTE:Shelflifeofthe EES explosivevalvesis 5 years. Anyexplosivevalveover5 years old mustbereplaced.
AfterusingtheEES,pneumaticpressurefromthesystemmustbereleasedandthe hydraulic systempurged.
(a)
Toreleasepressure,loosencaponteefittingserviceporttill thepressurerecedes.Leavethe caplooseonthe fitting.
(b)
Oncethedamageis corrected onthehydraulicsystem,connectthehydraulictestcart to hydraulictestports.
(c)
Usingthe test cart,cyclethegear to theDOWNpositionandat least 6 more timesto ensure theshuttlevalveandsystemisin the hydraulicmode.It may benecessary,dependingonthe
damagetothehydraulicsystem,to actuate thegearmorethan6 times to removeanyair in the system.
(d)
Retightenthecap on servicefitting.
(e)
Disconnectelectricalwiringandpneumaticlinefromexplosivevalveon the storagebottle.
NOTE: Onthe nosegear bottle, the teefitting mustbe removedfromthe explosive valve. Be sureto note that thefitting is installed with the test port inboard.
(f)
Installreplacementvalveon the bottle.
(g)
Reconnectelectricalwiringandpneumaticlinetotheexplosivebottle.
(h)
Chargebottlewithdrynitrogento pressure indicatedontheplacardmountedonthewheelwell nexttothefill valve(referto 32-30-00Figure1).
(i)
Performfunctionaltest covered in32-30-00.
4. FunctionalProofPressureandLeakTestForEES
(a)Supportaircraftonjacks.
(b)
Disconnectnosegearandmaingearstrutdoors.SecuretheminfullOPENposition.
(c)
Connecta hydraulictestcart (refer to 29-10-00) to the hydraulicsystemserviceports.
(d)Loosencapsfromtheteetestportsinstalledin the EESlinesleft and rightmaingearsandon theexplosivevalveon the nosegearstoragebottle.
(e)Activatehydraulicsystemthroughthetest cart andcyclethegearsixtimesto ensureshuttle valveisin the hydraulicmode.On the lastcycle,leavegearin the UPandlockedpositionand placegearselectorhandleintheneutral,DOWNposition.
(f)
Removecapfromtee test portattheleftmain gear. Connectanitrogensourceof 4000 to 5000psi(referto32-30-00Figure301).
(g)
Carefullypressurizesystemto2000± 50psi.
(h)
Ensureleftmain gear dooropensfully, the gearunlocksfrom the UPposition,andlowersto the DOWNandlockedposition.
(i)
Slowlyincreasepressurein the systemto3000± 50 psi and maintain for3 minutes while checkingtheshuttlevalves,the unlock, geardoor,and gear actuatorsfor leakage and deformation.
() Depressurizethesystem,disconnectalternatenitrogensource,andscrewcapontee fitting so excesspressurecanescape.
EFFECTIVITY: PAGE6
040-999
Jan10/9032-30-00
PIPER AIRCRAFT
PA-42-720(Advanced Trainer)
MAINTENANCEMANUAL
A. ExtensionandRetraction(continued)
12
11
11
Gear In Down and Locked Position With Doors Closed and Locked -Using Hydraulic,EmergencySystem Inactive. DOWN
1.
Door Closed Line 15. Left Main Gear Up Lock
2.
Door Open Line 16. Left Main Gear Actuator
3.
LandingGear Up Line 17. Left Door- Shuttle Valve
4.
LandingGear Down Line 18. Right Door- Shuttle Valve
5.
Nose Gear Bottle 19. Right Main Gear Actuator
6.
Shuttle Valve -Nose Gear 20. Right Main Gear Up Lock
7.
Unlock Actuator -Nose Gear 21. Right Main -Unlock Actuator
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