Testing altimeter and ASI

[Mriya]

Yes, the CAO s are being slowly phased out. What has it been replaced by, do you know?

Someone beat me in pointing out CAO 108.56 is now cancelled. You will find all the instrument calibration requirements embedded in an updated CAO 100.5

 

 

[Mriya]

Transponder not required for Class DCheers

 

John

Well done on finding the the flaw in my blanket statement. When making my statement was more concerned with the many RAAus aircraft that I suspect are flying in Class E without a current AD/RAD/47 check on their transponder.

 

 

[Mriya]

DafyddTheir point is valid imho. Within RAAus Aircraft I would guess that 75% or more use the Cheap non TSO'd altimeters. No LAME instrument fitter is going to issue a serviceability tag for these generally Chinese sourced instruments because there is no manual that defines the checks, the tolerances and the approved repair methods that are to be used if they need to be calibrated, nor at what point calibration via adjustment is actually needed. (Is the instrument out, or just sh!tty?....or more like reality its Sh!tty and out)

 

As such what determines whether a particular instrument is serviceable?

 

Andy

I would see a distinction between simply verifying an instrument against the standards in the RAAus TM / CAO 100.5 and getting an instrument repaired in a workshop. No problems confirming serviceability in the aircraft using a calibrated test box per guidelines in the CAO, however the moment the cheap chinese instrument fails no approved workshop will touch it without repair data. At that point you chuck it out and get a new one.

 

 

[Dafydd Llewellyn]

Someone beat me in pointing out CAO 108.56 is now cancelled. You will find all the instrument calibration requirements embedded in an updated CAO 100.5

Thank you.

 

 

[bilby54]

I wouldn't be to critical of the Chinese instruments as a lot of the instruments are made in the same same factory these days but some have a special piece of paper attached.

 

The problem with the cheaper variety is that if they are found to be faulty then it is cheaper to replace them than have them recalibrated. The small bearings and linkages that make up the instrument all wear and this is exasperated when the aircraft is mostly operated from grass or rough strips hence the reason to have them checked every two years. The electronic ones have their own set of problems that may be easier to recalibrate but I suspect will be more exspensive to do so. Testing is simple and really should be done at every hundred hourly

 

 

[jakej]

Transponder not required for Class DCheers

 

John

Not yet anyway but there is an NPRM or discussion paper on the requirement despite the last one stating no requirement - how quickly things can change

Jake J

 

 

[jakej]

I wouldn't be to critical of the Chinese instruments as a lot of the instruments are made in the same same factory these days but some have a special piece of paper attached.The problem with the cheaper variety is that if they are found to be faulty then it is cheaper to replace them than have them recalibrated. The small bearings and linkages that make up the instrument all wear and this is exasperated when the aircraft is mostly operated from grass or rough strips hence the reason to have them checked every two years. The electronic ones have their own set of problems that may be easier to recalibrate but I suspect will be more exspensive to do so. Testing is simple and really should be done at every hundred hourly

As I understand it you can't 'sign off' the repair of the Chinese or any make of Altimeter to FAR 43 Appen E (or F?) if there is no factory approved repair manual. There are soooo many of these that fail, I have known them to be DOA, that I'm surprised that anyone uses them anymore & that CASA allow their installation. They are an absolute waste of money IMO, and I've worked on a lot of aircraft. Customers can supply them if they want but I will never buy one until they are proven to be reliable and legally repairable

 

Jake J

 

 

[bilby54]

As I understand it you can't 'sign off' the repair of the Chinese or any make of Altimeter to FAR 43 Appen E (or F?) if there is no factory approved repair manual. There are soooo many of these that fail, I have known them to be DOA, that I'm surprised that anyone uses them anymore & that CASA allow their installation. They are an absolute waste of money IMO, and I've worked on a lot of aircraft. Customers can supply them if they want but I will never buy one until they are proven to be reliable and legally repairable Jake J

I should have qualified my statement as being for RAA aircraft only

 

 

[jakej]

I should have qualified my statement as being for RAA aircraft only

Thanks, that helps as many can be confused by the rules & what aircraft category they apply to.

 

 

[sfGnome]

Can I ressurect this thread to ask a related question? Our (*very* old) altitude encoder has curled up its toes and taken its last flight. The replacement choice from Australian suppliers when you're purchasing encoder only seems to be limited to the Ameri-King AK350 or the Microair EC2002. As our transponder is also Microair - and it's Aussie - , it seems to make sense to use it rather than the American unit. However, the Microair unit is not TSO'd. My understanding is that if a recreational aircraft is flying over 5,000ft, then it must have a transponder that has been calibrated within the last two years, but it is not necessary for the devices themselves to be TSO'd. Is that correct?

 

 

[frank marriott]

No requirement for transponder > 5000ft OCTA [although a good idea especially in busy areas]

 

Required in class E, generally LL 8500ft coastal.

 

TSO'd not reqired. RAD47 required for CTA.

 

Obviously output of blind encoder needs calibrating before using mode C.

 

 

[Mriya]

Adding to Frank's reply, depending upon the aircraft you are fitting it to will determine the type of approval process to allow fitment of different equipment.

 

Factory built LSA - manufacturer approval needed to substitute parts.

 

Full type certified - EO from a CASR 21 (old CAR35) engineer authorising fitment.

 

Experimental (various) - self approved.

 

As Frank rightly pointed out RAD47 check must be current before entering CTA where a txpr is required.

 

 

[sfGnome]

Thanks to you both.

 

 

[kaz3g]

and I to wonder about that too,,,,makes it a worry when someone gives an ALT in a position report and it could be wrong by a few hundred feet. In the Yarra Valley with two big airfields, a few private strips, helo ops at vineyards and meat bombers inbetween, tootleing around with a dodgy ALT because you didn't read the rules could kill people. I've stood on the ground and watched pilots waffle through the YCEM circuit and wondered if they're suicidal or just got the wrong altitude, I've seen a few near collisions from this and there has been a midair in the past in the circuit here!This is our biggest problem in RAA, we think the rules don't apply to us and then when big brother comes along and says well actually apart from a few exemptions the rules DO apply we all cry foul!

I heard an older pilot once say the Reg's are written" in the blood of pilots past", sounds serious doesn't it.

 

Matty

Too right, Matt

 

It's bad enough when everyone is doing the right thing at the right altitude...

 

I had a close call with a student who decided to join the downwind leg for 35 from the east at YCEM. I was doing touch and goes. In the circuit climbing out on crosswind and about to turn downwind I found him head on a VERY short distance away (all circuits east at 1500'). I had a discussion with the student and his instructor...the student had not seen me at all. He should have descended on the dead (west) side and joined crosswind into a full circuit. His short cut could hive proven fatal for both of us.

 

I also had a Jab heading into Lilydale fly under me quartering from the rear and less than 50' lower as I entered the downwind leg for 35. I did all calls as required. The minimum overfly height for YCEM is 2000 so go figure. I heard the pilot give her joining circuit call at YLIL and called her to tell her what she had done but, surprise, no response. I called in and told the GA CFI later on but never heard anything. After all this time and a mid- air in similar circumstances, you would reckon this would be writ large on everyone's forehead.

 

Kaz

 

 

[kaz3g]

No requirement for transponder > 5000ft OCTA [although a good idea especially in busy areas]Required in class E, generally LL 8500ft coastal.

TSO'd not reqired. RAD47 required for CTA.

 

Obviously output of blind encoder needs calibrating before using mode C.

I also use a Microair and it has proven very reliable.

 

Kaz

 

 

[DonRamsay]

Kaz, do you know if you have the Microair Alt encoder or something else like AmeriKing.

 

 

[kaz3g]

Kaz, do you know if you have the Microair Alt encoder or something else like AmeriKing.

I'll check and let you know, Don. I had the RAD done last year at Coldstream but not sure.

 

Kaz

 

 

[Mriya]

I'll check and let you know, Don. I had the RAD done last year at Coldstream but not sure.Kaz

I was involved in that inspection, however the rad47 criteria doesn't include applying a vacuum to the static system. Rad43 IFR checks go the extra step. Can't remember encoder details as it is not the focus of the check but do remember the microair system looks good in your aircraft.

 

 

[frank marriott]

A quick pilot check to confirm that your transponder is transmitting correct altitude information is to set your altimeter to 1013 and turn transponder to PA (pressure alt) and confirm that the reading is within 100ft.

 

This can be done in cruise, not just on the ground, to confirm it is linear up to 10000ft.

 

 

[DonRamsay]

I'll check and let you know, Don. I had the RAD done last year at Coldstream but not sure.Kaz

Thanks Kaz. We had an AK as original fitment in the P2002 and will just replace ours with the same to avoid any LSA issues.

 

 

[kaz3g]

I was involved in that inspection, however the rad47 criteria doesn't include applying a vacuum to the static system. Rad43 IFR checks go the extra step. Can't remember encoder details as it is not the focus of the check but do remember the microair system looks good in your aircraft.

Thank you! How are you all getting on at the MAF? Is the Sonex growing yet?

 

I haven't been able to get down for a visit for ages but hope to do so over my Christmas holidays. Please give my regards to the guys.

 

People here may not know that you have a very well set up workshop at Coldstream and that you run RAA as well as GA aircraft in your fleet.

 

Best wishes

 

Kaz

 

 

[Mriya]

Thank you! How are you all getting on at the MAF? Is the Sonex growing yet?I haven't been able to get down for a visit for ages but hope to do so over my Christmas holidays. Please give my regards to the guys.

 

People here may not know that you have a very well set up workshop at Coldstream and that you run RAA as well as GA aircraft in your fleet.

 

Best wishes

 

Kaz

Hi Kaz,

The sonex is slowly taking shape although the school students have now finished for the year. We also are getting close with the RV7A project (do you know anyone interested in purchasing it?). Only other news for us is David will be heading back up to MAF Gove soon and I will be taking on the chief engineer role here at Coldstream. I aim to build on the good work of David in establishing our workshop as a viable option for local customers other than our own FTC.

 

I am sure the YCEM flyers will be delighted if you are able to drop in at any stage and I'll be sure to pass on your greetings if I see any of them in the next little while.

 

 

[Bruce Tuncks]

If it is only required to test the altimeter to 10,000 ft , then this could be done with a water manometer. The suction pressure corresponding to 10,000 ft is 3 metres of water which is a bit inconvenient but not that hard to achieve. It would best be done on a cool day, to lessen vapor pressure concerns, but this would not be essential. Yes you would need a step-ladder and a tape measure.

 

Water manometers are better than a calibrated ASI for checking the ASI, so there should be no objection to using one for the altimeter.

 

Of course a mercury manometer would be much smaller, but mercury is more expensive than water I bet.

 

There are other fluids with densities about double that of water, but I don't have any of those around either.

 

 

[jakej]

Mriya - call me I know of someone but depends on engine/equipment etc. 0412 624 723

 

 

[Camel]

I've been looking at Manometers on eBay, has anyone bought an electronic manometer and are there any suggestions, I know I can make a simple water one.