Decision Height Settings

[Fall_guy 1]

Hi Guys,Does anyone happen to know,...... how the decison height is set in most modern aircraft.Ideally where the knob/dial is most commonly located that sets this height.also I'm not sure if this is linked to the above question!!, but what exactly is the BUG reference associated with on the Altimeter (Not the Baro). Anyone know what this is for?Finally can someone please explain what the TRIM Failed annunciator means. When is it displayed and what failure does it notify you of.Any help would be grately appreciated.Cheers John

[Roger Mazengarb 0]

G'day John,>Does anyone happen to know,...... how the decison height is>set in most modern aircraft.Im not with you on this one. Do you mean "how the decision height is determined"?>Ideally where the knob/dial is most commonly located that sets>this height.Simple answer - wherever the designer puts it.The glare shield panel is a commom place but not the only place.See the attachment for the B717 location.>>also I'm not sure if this is linked to the above question!!,>but what exactly is the BUG reference associated with on the>Altimeter (Not the Baro). Anyone know what this is for?Again see the attached pic. If you are referring to the digital setting on the PFD then it may well be the decision height.>Finally can someone please explain what the TRIM Failed>annunciator means. When is it displayed and what failure does>it notify you of.Straight from the KFC (not Kentucky Fried Chicken) manual. :-lol " The trim warning light in the annunciator panel will light when a monitored auto or manual electric trim failure occurs or when the trim breaker is pulled. It will also flash 4 to 6 times when the TEST switch on the mode controller is depressed to indicate proper operation of the Auto trim monitor feature."Again this info is for the King KFC 250 integrated Flight Control system.>>Any help would be grately appreciated. Cheers,Roger @YSSY

[Roger Mazengarb 0]

G'day John,Duh!! forgot to post the pic so here it is.I take it all your questions relate to the MD-83.Cheers,Roger @YSSY

[Fall_guy 1]

Hi Mate,What picture!!!! (ha,ha)Anyhow Ive posted a couple of pics for your attention. The altimeter bug (marked in red) and a panel annunciator/warning light (I'm not 100%, but it looks like FD / dacs??).........any ideas.Finally I really do appreciate your invaluable help and was wondering if you'd be up for Testing my creation. Is just that time becoming short now and I need someone to fly her around while I'm tidying up, so we can make her available in the near future.Im nearly finished intalling the built in vocal warning systems and a few other goodies..............WHOOPS nearly forgot!!At what point do the Pilot / coPilot refer to CROSScheck during takeoff.Are they checking Speed indication??CheersJohn

[Fall_guy 1]

Hi Roger,Yes.... I was refering (trying to refer) to the actual location of the Knob that sets the Decision Height. Now I can see your picture and where you've located yours.Its just that I could'nt see a knob anywhere on several panel pictures that could possible be the decision height setting knob. I was beginning to think it maybe on the overhead?Thanks again MateJohnBy the way I think your panels really good!!

[Guest Eagle]

John, if you are looking for someone to test your aircraft I would be more than happy to do so.

[Roger Mazengarb 0]

G'day John,>>What picture!!!! (ha,ha)>>Anyhow Ive posted a couple of pics for your attention. The>altimeter bug (marked in red)That certainly looks like a decision height setting bug but I'm not 100% sure. ( I'll ask a few questions and get back to you)> and a panel annunciator/warning>light (I'm not 100%, but it looks like FD />dacs??).........any ideas.That's FD/CADC. The Central Air Data Computer is used to convert pitot/static pressures into electrical signals that can then be used by avionics systems (ie. Flight Director, Auto Pilot, Flight Management Computer, Instruments etc). That's why you will still find a standby (pitot/static pressure) Altimeter/ASI on some glass cockpits because if the CADC fails you would lose all height/speed referrence. >Finally I really do appreciate your invaluable help and was>wondering if you'd be up for Testing my creation. Is just>that time becoming short now and I need someone to fly her>around while I'm tidying up, so we can make her available in>the near future.Mate I'd love to test her out for you. When you are ready email me rogermaz@idx.com.au>Im nearly finished intalling the built in vocal warning>systems and a few other goodies..............WHOOPS nearly>forgot!!>>At what point do the Pilot / coPilot refer to CROSScheck>during takeoff.>Are they checking Speed indication??I'm not a pilot but there is no point in checking one ASI instrument against the other for ACCURACY. (you wouldn't know which is right and which is wrong anyway)and whoops too late; you're past V1 and committed to take off regardless. The last thing a pilot needs during take off is a distraction. It only confuses them :-lol and they usually end up in a mess off the end of the runway. True; even engine fire warning is inhibited on take off. The first thing a B747-400 pilot would know about an engine fire on take off would be at 400 feet (the height at which the inhibit is removed) when all hell would break loose in the cockpit. :-) There is no actual "airspeed value" that is checked but they may simply call "aispeed active" purely to verify that the system is working (ie. some idiot *:-* hasn't left the pitot covers on :-lol )Notwithstand all the above, individual airlines may have it in their take off produre to call "airspeed" at a certain value. BUT it is still rather a system verification On final approach however cross checking the Altimeters is good insurance as this will pick up differences in QNH settings.( They should of course be the same). Also it confirms both altimeters agree on the aicrafts height. Cheers,Roger @YSSY

[Roger Mazengarb 0]

G'day John,>Yes.... I was refering (trying to refer) to the actual>location of the Knob that sets the Decision Height. Now I can>see your picture and where you've located yours.I didn't put it there! Boeing did! Thats a photo of the glare shield of their B717. On older aircraft the decision height can be found on the altimeter itself but once you upgrade to a VDU screen the manufacturers had to find a spot to place the adjust knobs for both QNH and decision height and you can see in the photo where Boeing have put them for their B717 model.Cheers,Roger @YSSY

[Fall_guy 1]

Hi Wayne,Thanks for your offer.................Although it maybe a while yet before I can figure out how to hook up some of the systems. If you still want to test her out drop me an email and I'll be intouch.ThanksJohn