kortopates Posted March 29, 2022 Report Share Posted March 29, 2022 1 hour ago, carusoam said: Delete button is hiding at the top of the post under the “…” looking thing… -a- thanks Anthony, but don't have that option in Tapatalk (unless I am missing something) - just on the web where I am now so can do it. Tapatalk does offer a webview function - that might work to get me there. 1 Quote Link to comment Share on other sites More sharing options...
A64Pilot Posted March 30, 2022 Report Share Posted March 30, 2022 22 hours ago, kortopates said: JPI allows setting up Pre-alarm messages; such as a CHT alarm at 400F versus the factory limit. Unfortunately, the many options for these don’t include oil pressure. https://www.jpinstruments.com/FAQCategory/primary-instrument-alarms/ Sent from my iPhone using Tapatalk Understood, but I don’t believe you can raise the RPM redline so it won’t alarm if you exceed 2700 by a tiny amount, but we need to. I ran into the same problem with P&W turbines, you had two options, set RPM a little low which isn’t good as your reducing HP, or deal with nuisance alerts which isn’t good because your conditioning the pilot to ignore the red flashing lights he sees often. As I was in on the Certification of the GE-H80 turbine, I was able to talk the GE folks into yellow ranges for transient over speeds, over torques so it has no green range that suddenly turns red, you get into the yellow that tells you to slowly back off, but you didn’t have an exceedence, you were warned by a yellow range Everything I can think of in Military helicopters has transient limits, for example 100% torque was max, but I was allowed up to 115% for 6 sec Lycoming and Continental need to update their limitations, we are living in a digital world now and measuring things down to a gnats behind, they should allow transient, time limited over speeds in their limitations so these new digital instruments don’t nuisance alarm so much. An opinion of course 1 Quote Link to comment Share on other sites More sharing options...
PT20J Posted March 30, 2022 Report Share Posted March 30, 2022 The problem is that some engine monitors confuse gauge markings with alarm limits. The gauge markings are in the limitations section of the AFM and must be duplicated in the engine monitor when it replaces a factory gauge. Unless the aircraft was certified with an alarm, any alarms you set would be advisory and you could set them as you wish. However, you have no options to do so if the engine monitor ties the alarm directly to a required gauge marking. 1 Quote Link to comment Share on other sites More sharing options...
A64Pilot Posted March 30, 2022 Report Share Posted March 30, 2022 (edited) 9 hours ago, PT20J said: The problem is that some engine monitors confuse gauge markings with alarm limits. The gauge markings are in the limitations section of the AFM and must be duplicated in the engine monitor when it replaces a factory gauge. Unless the aircraft was certified with an alarm, any alarms you set would be advisory and you could set them as you wish. However, you have no options to do so if the engine monitor ties the alarm directly to a required gauge marking. I talked to Rob Roberts about that and the FAA was requiring if an instrument had an alarm, that it alarm at the factory limitations, which makes sense, because of course your exceeding a limit at that point. The issue is that the way the limitations are currently written, normal ops is right at the extreme edge of max allowed, so that any tiny bit over is an overspeed and must trip an alarm. FAA can’t/won’t back off as if the do they are encouraging over limit ops. So in my opinion the engine manufacturers need to look at their limitations, cause we aren’t going back to round analog gauges with no recording or alarms. Back when my Father was flying his C model these limits made sense as the pilot was the determining factor on if an exceedence was occurring or not and a momentary blip past 2700 was of course ignored, if it was even noticed I’ve never flown any of the fancy new glass like the G1000’s etc. how do they handle the issue? Surely they don’t nuisance alarm? Yeah, I know G1000 isn’t new, unless you old. Edited March 30, 2022 by A64Pilot Quote Link to comment Share on other sites More sharing options...
PT20J Posted March 30, 2022 Report Share Posted March 30, 2022 4 hours ago, A64Pilot said: I’ve never flown any of the fancy new glass like the G1000’s etc. how do they handle the issue? Surely they don’t nuisance alarm? I explained how the G3X Touch EIS handles this earlier in this thread. The STC requires that the instrument markings agree with the AFM/POH/TCDS but recommends setting alarm limits slightly above/below the limits, and there is no requirement to set any alarm unless it is replacing an existing annunciator in which case the existing annunciator is supposed to be removed, or disconnected and placarded disabled. Quote Link to comment Share on other sites More sharing options...
A64Pilot Posted March 30, 2022 Report Share Posted March 30, 2022 18 minutes ago, PT20J said: I explained how the G3X Touch EIS handles this earlier in this thread. The STC requires that the instrument markings agree with the AFM/POH/TCDS but recommends setting alarm limits slightly above/below the limits, and there is no requirement to set any alarm unless it is replacing an existing annunciator in which case the existing annunciator is supposed to be removed, or disconnected and placarded disabled. Well then I guess Garmin broke the code, and other manufacturers will hopefully soon follow suit? Quote Link to comment Share on other sites More sharing options...
kortopates Posted March 30, 2022 Report Share Posted March 30, 2022 5 hours ago, PT20J said: I explained how the G3X Touch EIS handles this earlier in this thread. The STC requires that the instrument markings agree with the AFM/POH/TCDS but recommends setting alarm limits slightly above/below the limits, and there is no requirement to set any alarm unless it is replacing an existing annunciator in which case the existing annunciator is supposed to be removed, or disconnected and placarded disabled. I am not sure I understand what you mean by alarm limits. Is it not an alarm when the engine monitor reports a limitation/redline has been exceed. I don't know of any that don't annunciate in some way but usually in the form of a light and text message. What I see the new airframe manufacturers (e.g. Cirrus and Cessna) doing is setting max RPM targeted at 2680 rather than 2700 rpm to avoid nuisance alarms when it hits 2700. The goal is to get close without alarming. The thing I hate is some engine monitor company's have added arbitrary limits when none exist, such as 1600F for EGT. Sure it likely means something is not right when you see an EGT hitting 1600 in normal cruise since its likely means there is a cold plug, but it'll alarm when the pilot does a Mag check in flight and the pilot thinks something is going to burn up. Maybe my issue is really more about how it alarms without enough distinction between cautionary (yellow) versus limitation (red) alarms, This sort of thing doesn't stop with the engine monitor folks either. Mooney did the same thing by creating an arbitrary limit on fuel pressure way below Lycoming's limits at 30 psi. All was fine till Lycoming made a design change improvement to their engine fuel pump which resulted in the fuel pressure exceeding 30 psi. Still way below Lycoming's acceptable range max limit but above their POH. I still don't get why Mooney hasn't provided a SB or SL to raise their limitation since their 30 PSI limit is arbitrary. I know they have gotten lots of mail about it. 1 Quote Link to comment Share on other sites More sharing options...
PT20J Posted March 31, 2022 Report Share Posted March 31, 2022 4 hours ago, kortopates said: I am not sure I understand what you mean by alarm limits. Is it not an alarm when the engine monitor reports a limitation/redline has been exceed. Paul, my point was that originally airplanes with mechanical gauges just had markings and an accuracy of about +/- 1-2%. Most of the things they measure also have an accuracy on the same order. There is no need to be overly precise about setting alarms when the precision exceeds the accuracy of the measurement. Depending on conditions, my engine turns between 2680 and 2705 rpm on takeoff. That’s normal. I don’t want an alarm at 2700. 2750 would make more sense. Nuisance alarms are really a very bad thing because they condition us that an alarm is a normal condition and they then tend to be ingnored. I want all my alarms to mean that there is really a problem. Skip 3 Quote Link to comment Share on other sites More sharing options...
carusoam Posted March 31, 2022 Report Share Posted March 31, 2022 Some individual people are really good at gauges and alarms… and FAA regulation… Some people have taken engineering sense and thrown it out the window…. -1 for the organization that found and alarm at 2701 to be an annoyance… and set the RPM lower to avoid the alarm… The RPM is a source of power… I paid extra to have the 2700rpm red line… I don’t want a 10rpm bandaid… that would be bad form… for a plane that costs as much as a house… The 2700rpm gets me off the ground in a known shorter distance… When I move to the JPI900 or similar from EI… I’ll pay extra and get annoyance alarms… during the T/O roll… Nuisance alarms during the T/O is a really bad time to have them…. My eyes are already scanning things outside the cabin… If there is an alarm going off… I need to know to stop the T/O roll…. Not guess or assume it is only an annoyance… or ignore because it is always there… I already have a few things going on to check… MP, RPM, and FF… and the Kias are climbing…. Staying on the centerline is still important… Wonder how the EI guys handle nuisance alarms… People like @oregon87 know instruments, airplanes, and the FAA…. (What does it take to avoid having nuisance alarms go off on EI equipment, mounted in Mooney Airplanes….?) Engine monitors have come a long way since they first burst on the scene decades ago… Follow up question… Is EI at the Aircraft Electronics Association show this week? Best regards, -a- Quote Link to comment Share on other sites More sharing options...
atpdave Posted March 31, 2022 Report Share Posted March 31, 2022 On 3/30/2022 at 5:12 AM, A64Pilot said: I’ve never flown any of the fancy new glass like the G1000’s etc. how do they handle the issue? Here is how the Ovation 2 G1000 handles tach alarms: Pages from 09 Supplemental Data.pdf 1 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted March 31, 2022 Report Share Posted March 31, 2022 Fantastic details ATPD! It specifically states how to handle the nuisance alarms… during T/O! Share that with the engine monitor folks... @oregon87 (something that may be of interest to your alarm handling people during T/Os… direct from G1000 Mooney supplemental data.) Best regards, -a- Quote Link to comment Share on other sites More sharing options...
A64Pilot Posted April 1, 2022 Report Share Posted April 1, 2022 See the manufacturer wrote limits to accommodate the new gen instrumentation, Lycoming and Continental should come on board and re-write their limitations to accommodate the new instrumentation. I assume those limits came from Mooney, with the engine manufacturers support? Garmin apparently has broken the code as reported earlier with the G3X if I stated that correctly, maybe now all the other manufactures can follow suit and allow the operator to set alarms? We still fly behind our Grandfathers engines, but we don’t monitor them with his gauges 1 Quote Link to comment Share on other sites More sharing options...
oregon87 Posted April 5, 2022 Report Share Posted April 5, 2022 (edited) Apologies for the delay in responding. Depending on what is happening around the office, I don't always have the time I'd like to frequent the forums. The "legal" answer is that if any of our instruments are to be installed in a certified aircraft, the manufacturer's specified red and yellow ranges must be followed. Having said that, we also understand that the manufacturers sometimes get it wrong and provide ranges that may have been appropriate for analog gauges, but not for more advanced and more accurate instrumentation. At a minimum, inappropriate ranges were far easier to ignore with analog gauges. As we absolutely understand the safety concern of nuisance alarms, an A&P or IA can contact us to make a change outside of the specified ranges, if they are willing to certify the ranges (if required) and sign off on doing so. This releases the liability from E.I. and basically puts it on the IA/A&P as they have the authority to make such changes. Edited April 6, 2022 by oregon87 2 1 Quote Link to comment Share on other sites More sharing options...
carusoam Posted April 6, 2022 Report Share Posted April 6, 2022 Fantastic detail @oregon87! Better late than never!! Thanks for sharing it…. Best regards, -a- 1 Quote Link to comment Share on other sites More sharing options...
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