skullcap Posted April 10, 2013 Report Share Posted April 10, 2013 I think some of you need to reread the initial report. The problem is that the N1 is limited to 95%, N2 is drooping with any increase in collective pitch beyond the power setting equivalent to 95% N1. Incorrect autorotation rpms will have zero effect on N1 topping. Incorrect setting of autorevs will have transient droop issues and perhaps a slight static droop but not a continuous loss in rotor rpm with the N1 limited to 95%. They have as meantioned adjusted the fuel flow on FCU probably too much and should have N1 out the ying yang. So this tells me there is a fuel limiting situation, pump probably, maybe nozzle, maybe something else. Waiting with baited breath. Quote Link to comment Share on other sites More sharing options...
RTR Posted April 10, 2013 Report Share Posted April 10, 2013 The Max stop on the fuel control should not be adjusted. It is set at overhaul, Just a FYI. As far as rotor drooping at 95% N1...it does sound like you have a low flow rate for higher powere settings. Seeing as how you have already tried swapping out the fuel control with no change , the Engine driven fuel pump seems a likely culprit.. I'm with Skully on this one. Be interesting to see what it ends up being. RTR Quote Link to comment Share on other sites More sharing options...
Lunchbox Posted April 10, 2013 Report Share Posted April 10, 2013 Have the relevant gauges been checked or swapped with another aircraft? Seen it before where pretty much all engine components are changed, but it turns out the gauge was wrong all along. Quote Link to comment Share on other sites More sharing options...
skullcap Posted April 10, 2013 Report Share Posted April 10, 2013 Am thinking that since the power check numbers are ok for tot that the n1 gauge is ok. If tot was through the roof and torque gauge reading 128 % and N1 only 95 % would be indicative of the N1 reading low. Quote Link to comment Share on other sites More sharing options...
justinengineer Posted April 13, 2013 Report Share Posted April 13, 2013 How are you making out Lineworker? Quote Link to comment Share on other sites More sharing options...
DGP Posted April 13, 2013 Report Share Posted April 13, 2013 I haven't worked or flown a 206 for awhile but I am sure the N1 should hit 104% before you have droop...reminds me of a pilot that thought he had a sick engine as it was unabale to lift off the ground at 100% torque with 2 guys on board.....I asked him what the N1 was....he said 104%...next question...what was the oat....he says 34C....how much fuel....full tank with range extender full....elavation.....I think he said either 8000 or 10000...it was Mexico City...I then said... what do you think!!!....my guess was you better lighten the load...if the fuel flow is set correct on the fcu.and the idle speed is set correctly and the max stop is correct...it is probably one of 3 gauges reading incorrect....you can check the fuel pump by metering fuel into a container and checking the flow rate as per the MM....auto speed will also vary with engine idle speed....somewhere between 62-65% should have the needles splitting....92% was mentioned ....this changes with idle speed....should have nothing to do with droop....most bendex governors will maintain rpm better than a ceco....if properly rigged....I have seen way to many droop compensators on 206 that should have been thrown in the trash bin....usually bendex govs arms are as loose as a goose and are not binding...they have a bleeder vent on them which could be acting up....they get very black looking when things are acting up....looking forward to the results of the investigation. Quote Link to comment Share on other sites More sharing options...
lamanated Posted April 15, 2013 Report Share Posted April 15, 2013 how many hrs on the gov? can you swap them? I have seen once a bleed at the throttle shaft bushing at high power settings. most gov's on 206 seem to die a hr after warranty on a 206. Call Mike senior at essential,. Quote Link to comment Share on other sites More sharing options...
skullcap Posted April 15, 2013 Report Share Posted April 15, 2013 Jetranger 3 N1 limit is 105 n1, so wont droop until above that. Really don't think are that high so that is issue. Highest I have seen N1 on JR3 is 102 at close to 11,000 ft. They have various aircraft operating off the airport including an R22 so my guess is lower elevations. Gov has been overhauled and changed with another machine, re first post. Quote Link to comment Share on other sites More sharing options...
whirlygig Posted April 15, 2013 Report Share Posted April 15, 2013 ....if properly rigged....I have seen way to many droop compensators on 206 that should have been thrown in the trash bin... FYI.... The Droop compensator is NOT the power turbine governor, it is a series of cams and arms within the governor linkage that compensates for droop. The system adjusts the ratio of governor arm movement per movement of the collective control. Quote Link to comment Share on other sites More sharing options...
skullcap Posted April 15, 2013 Report Share Posted April 15, 2013 FYI.... The Droop compensator is NOT the power turbine governor, it is a series of cams and arms within the governor linkage that compensates for droop. The system adjusts the ratio of governor arm movement per movement of the collective control. Am thinking he means the jack shaft anticipator thing, on older models was cable, newer is shaft from collective pitch similar idear as astar. Quote Link to comment Share on other sites More sharing options...
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