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LecLightning56

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Posts posted by LecLightning56

  1. 9 hours ago, scoobflight said:

    Is this when first engaging VNAV? After a slight turn in at a waypoint?  After a significant turn at a waypoint?  Details please.

    This happens after a significant turn at a waypoint. The aircraft seems to oscillate around a bit laterally until it finally settles down on the NAV track determined by the flightplan.

  2. I have this problem still with the v3 aircraft in the SP1 update. The aircraft seems to respond slowly to the NAV course almost as if it is hunting for the right track. Does anyone else have this issue and has anyone managed to resolve it?

  3. Guys,

    With the recent release of the SP1 update I have revisited the steep approach scenario again (London City EGLC) and have made some interesting discoveries.

    First and foremost, the A/T maintains constant speed throughout the steep descent once having captured the localizer and glideslope with the SP1 release, whereas previously the speed increased quite dramatically. I do appreciate of course that the FeelThere EJets are not strictly steep-approach compliant on account of an inability to deploy the speedbrakes for such approaches, as is the case for real-world aircraft which have gained such certification. 

    Secondly, as an experiment I happened to note that the response of the FeelThere aircraft to capturing the glideslope was slightly sluggish and the aircraft would remain slightly high on the glideslope initially (i.e. above the prescribed flightpath for the approach) and with a consequent higher vertical speed than should be the case if following the glideslope correctly. I then decided to experiment with the Touch Control Steering (TCS) with interesting results. If you arm the localizer and glideslope and wait until the glideslope diamond indicator has dropped to just one notch above its centered position for the correct glideslope then immediately use TCS to drop the aircraft gradually (but not too abruptly) to a flightpath angle of about 4 to 5 degrees pitch down (with autopilot still on), there reaches a point where the glideslope is captured completely and no further TCS inputs have any effect. If you then release the TCS button on your yoke or joystick, the aircraft follows the glideslope exceptionally well. Whereas I am sure that this may not be a correct procedure for glideslope capture in the real-world for very good safety reasons (correct me if I am wrong), but the use of TCS with the FeelThere EJets does seem to be beneficial in maintaining the correct glideslope on a steep approach. For London City there is no certification for autoland, but the approach can be flown safely if you fly to the minimum decision altitude before manually landing the aircraft and with the autothrottle selected throughout by the means described.

  4. 12 hours ago, Triholer said:

    Hey, 

    even though I‘m not part of the feelThere-Team, I can assure you that the E-Jet Autothrottle is not always a real help on the real aircraft as well. 
     

    The real A/T is a little bit slow on the compensation of changes (keep in mind, that even the 737 is not quite perfect there), but especially it has a tendency to rather go a little bit under the selected speed than above it - so for your calculations be rather pessimistic und choose speeds a little higher than you‘d usually choose. 

    Therefore in our operations we stand to use our hand as a backward limit to the throttle, manually overriding it regularly. Especially in gusty conditions I would not trust the real A/T doing its business alone and by the calculated values. We do always override, but still keep it on as a safety net. 
     

    By the way, what is your weight in the scenario? I do fly the E190 myself and know the E170 only from the Simulator, but 115knts - especially in a turn - sound really low to me. 
     

    Best Regards
    Björn

    Thanks Bjorn for the benefit of your own personal experience with the real aircraft, which is only for the good in terms of educating we earthbound mortals about how things really are.

    The weight in my scenario is indeed low, with about 35% fuel and no passengers and cargo, (approximately 55,300lbs GW, sorry about imperial units). I am inclined to agree that for turning flight at such a low speed of 115 kts that the A/T may be endeavoring to maintain the speed but at the cost of not being able to provide the increased thrust to counter the increase in drag and hence the corresponding loss in altitude in order to maintain the speed itself, which I hope is correct A/T logic under such circumstances although certainly not to be entertained under real-world conditions. 

    On the subject of the RNAV transition to London City EGLC RW09 (ODLEG 1G), I have repeated this with more realistic speeds for the turns associated with intercepting the localizer and things do play out very much better now. I need to practice this more carefully to get to grips better with the automation within the EJets but otherwise I am satisfied that I may have simply been putting impossible demands on the aircraft which probably even a real-world aircraft would struggle with to say the least (best not to live dangerously at low speed, low altitude when already at high power anyway). 

  5. 11 minutes ago, scoobflight said:

    Slow autothrottles is a known issue in the real world Ejet.  The response was moderated further in SP1 from original release after real-world pilot recommendation.

    Interesting indeed. I did note that, although the FeelThere EJets are not configured for such procedures, for a steep approach to e.g. London City, the A/T manages to keep constant speed throughout the glideslope capture whereas previously the speed increased significantly during the descent.

    It would however be useful if your real-world contacts could verify my findings that real EJets suffer such issues in reality, or if further tweaking may be required in the FeelThere flight dynamics to tighten up on the aircraft's ability to remain stable in a turning manoeuvre under automated control.

  6. Progress at last. It would appear that if I disarm A/T and control speed with the throttle lever, irrespective of considerations of v+10 knots for full flap (e.g. maintaining VAPP=115 knots), then altitude remains fairly constant in a turn or at least what could be determined as acceptable. So A/T seems to be the key player in the problem I have got, and is best disarmed when tight turns are flown at low speed and low altitude. This does seem a bug of sorts since I have proved that there is no necessity to increase speed with A/T off in order to maintain constant altitude in a turn. Puzzling why the A/T has this influence when it otherwise maintains constant airspeed as selected (as it should).

  7. Yes it does look as if increasing speed maintains constant altitude in a turn with AP and A/T on but I am not convinced that this is standard procedure and would be aghast if I had to be quite so alert with e.g. the 2000 feet turn for London City (the problem has nothing to do with steep approaches).

  8. 24 minutes ago, scoobflight said:

    Have you tried as I recommend?

    No. I am surprised that aircrew may have to be alert to this on a fully automated system particularly when their workload is excessive positioning the aircraft on the final stages of an approach. I am not aware of any other airliner which would require this degree of intervention in order to maintain constant altitude with an automated system. Is your recommendation in keeping with real world practice for this aircraft?

  9. 9 minutes ago, scoobflight said:

    Only at Flaps full?

    Try increasingly airspeed.

    Not being a real world pilot but I might have expected that the AP might be man enough to keep the flight parameters within tight bounds. Is it normal practice to increase speed even with AP selected in order to maintain constant altitude in a turn with the EJets?

  10. No, the aircraft is configured in the approach configuration with flaps fully extended. I am merely executing a turn using the heading select knob with AP and A/T on and the aircraft suffers excessive height loss. I am prepared to accept if I am doing something wrong which is causing this issue, but at the moment the behaviour seems disconcertingly unsafe.

    I just tried a fairly major heading change at 3000 feet which resulted in a height loss of 1000 feet. The aircraft eventually recovers back to 3000 feet in due course.

  11. Unless I am doing something very wrong, but I am experiencing significant height loss in a turn with the 170 in the full flap, gear down configuration with the autopilot and autothrottle on.

    I took the 170 up to 3000 feet, slowed down to approach speed (about 115 knots), selected full flap and gear down and then changed the heading. This resulted in a very significant height loss of about 500 feet. I recently tried a STAR arrival to London City EGLC with the 175 and experienced the same dramatic behaviour, which approaching EGLC at 2000 feet for an ILS to RW09 (again full flap gear down at 115 knots) is just not safe. With the latter case I was using LNAV and VNAV from a flight plan driven by the CDU. Hopefully I am doing something wrong which explains everything easily and I sincerely hope that this is not a major shortcoming of the product.

  12. 2 hours ago, aua668 said:

    Hi,

    What should trigger this action? airspeed, time, weather, taste of the beer you are drinking?

    Maybe you can specify your need a little bit more excactly. LUA functions can extend and retract flaps by one notch using for example the ipc.controls for:

    65758   FLAPS_INCR
    65759   FLAPS_DECR

    Rgds
    Reinhard

     

    Thanks Reinhard. I had missed the availability of ipc.control in the FSUIPC Lua Library manual to send a control and in this case it has solved my problem: I can now automatically decrement the flap setting based on height above ground level. Thanks again for pointing me in the right direction.

  13. 17 minutes ago, aua668 said:

    Hi,

    What should trigger this action? airspeed, time, weather, taste of the beer you are drinking?

    Maybe you can specify your need a little bit more excactly. LUA functions can extend and retract flaps by one notch using for example the ipc.controls for:

    65758   FLAPS_INCR
    65759   FLAPS_DECR

    Rgds
    Reinhard

     

    Long story. I have modified an aircraft.cfg to account for the additional drag of spoiler extension for the purpose of steep approaches with the FeelThere Embraer E-Jets v3. This may necessitate retraction of the spoilers at a specified altitude AGL (above ground level, or radar altitude) prior to touchdown (at which point the spoilers should deploy by default). The trigger here would be the aircraft altitude AGL (already calculated in a lua file by myself) which decrements the flap position by 1 notch at this specified altitude to account for removal of the aerodynamic effect of the spolers: in real life the retraction of the spoilers is automatic (too much going on very close to the ground for aircrew to be worrying about the spoilers in addition to safety considerations if they had been left deployed), and hence the requirement for automatic retraction in the sim world in the absence of actual keypress or button usage would also be advantageous.

  14. Probably stating the obvious, but if you disable the First Officer's PFD and MFD gauges in the VC by way of commenting out the appropriate lines in the panel.cfg file, there is a fairly hefty FPS gain on my quite high-spec system. This is akin to what you can do with most of e.g. the PMDG range of aircraft and it can help FPS significantly.

  15. I have done a little experimentation with the steep approach to London City. Clearly the real world aircraft has a ventral speedbrake to facilitate the steep approach which we cannot obviously simulate. So, what I have done is I have modified the aerodynamic coefficients for maximum flap deployment in the .air file for e.g. the 170 to account for the effect of a speedbrake in this configuration. If you initiate a 8nm final to London City at a VAPP of approximately 120 knots, the glideslope is captured by the aircraft with initially speed increasing by a few knots, then speed reducing to VAPP once the glideslope is stabilised correctly (the aircraft is initially high and lags a little in manoeuvring to establish on the glideslope which results in initially a steeper approach path and hence increasing speed: this is corrected later with the speed reducing back to VAPP).

    I cannot recommend that anyone fiddles with the .air file for these aircraft, but what I have done only applies to full flap deployment. The use of full flap is presumably more advantageous for the London City approach to achieve the slowest speeds for the shorter runway. The changes to the aerodynamic coefficients do not apply to other flap settings e.g. flaps 5 if the definitions of CL, CD and Cm in the .air file are correct.  If anyone is interested in what changes I have made then please PM me.

  16. 5 hours ago, raam123 said:

    Ok, an update.

    Since Matty post https://forum.simflight.com/topic/88367-speed-constraints/ I managed to do some testing.

    I deleted all FSUIPC configs and made a new profile and it seems to fix the GtS issue.

    I still need to test at EHAM , tested in LLBG (TLV) both 170 & 190 and all was great.

    Thanks raam123. I deleted my FSUIPC config file and retested, this time with success (no problems with glideslope capture and adverse behaviour). It is puzzling why profiles not associated with the E-Jets (in my case) have caused conflict with its approach behaviour where glideslope capture is concerned.

  17. 9 hours ago, Matty260191 said:

    No sorry i was wrong but it will stay at vapp with full flaps 

    I might be interested in the product if you feel it can stay at Vapp on e.g. an ILS approach to London City (approximately 5 degrees glideslope?), and not deviating above or below the glideslope path. What is your experience?

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