When is a NDB approach not an NDB approach?

[Tee Emm]

Question for the airline experts. Let's say the IRE requires you to conduct an NDB approach during an instrument rating test. Your aircraft is dual GPS equipped with a sophisticated state of the art flight management computer system. You are told by the IRE to conduct the NDB approach on autopilot coupled to the flight management system so the aircraft is actually flying a dead accurate track using the GPS updated FMS. In other words the instrument rating test to tick off the NDB approach is not a test of the competency of the pilot flying an NDB approach but more a test of his skill at monitoring an autopilot that gets its information from sources other than an NDB needle.

Question 1. Is this method a valid skill test of the pilot to fly an NDB approach using both vertical and lateral tracking via an FMS updated by a GPS?

Question 2. If not, would it be correct to say that the original intent by the regulator for initial issue and renewal of an NDB approach during an applicant's instrument rating test was to test the applicants ability to fly an NDB approach without the use of other navaids apart from the DME.

Note: I understand that GA ATO's are not permitted to allow candidates undergoing instrument rating tests to use autocoupled GPS tracking for the NDB competency test. That being so, one wonders why CASA is inconsistent in their regulation of instrument rating tests especially as the CIR is not type specific.

[Checkboard]

Remember ALL laws, rules and procedures are simply written by normal people - they are not the word of God! As the IRE standards were probably written before GPS coupled autopilot & FMS tech was good enough to fly the approach, then your answer is simply "As the rule is silent, it's down the to examiner's interpretation and good sense."

The purpose for the test is to see that the pilot can conduct a safe approach. If the pilot is a professional, pretty much ONLY flying one type - then yes, it is perfectly valid to watch them fly a safe approach in that type using the tools available (and the pilot still has to interpret the needle, to monitor the approach).

If the examiner thinks the candidate is going to run off after the test and fly a piston twin with no autopilot and nothing but a raw data needle - then that is the standard they (well, I) would want to see - but both are valid and legal.

[nitpicker330]

You can fly it upside down if you like AS LONG AS YOU MONITOR THE RAW DATA.:ok:

[swh]

Note: I understand that GA ATO's are not permitted to allow candidates undergoing instrument rating tests to use autocoupled GPS tracking for the NDB competency test. That being so, one wonders why CASA is inconsistent in their regulation of instrument rating tests especially as the CIR is not type specific.

Sounds more like an inconsistency with the ATO rather than CASA, CAO 40.2.1 says "An autopilot or a coupled approach may be used in the demonstration of proficiency in instrument approach procedures. However, the applicant shall also be required to demonstrate proficiency in instrument approach procedures without the use of the flight director and without the autopilot engaged in aircraft where this is permitted."

[nig&nog]

My last two jets didn't even have an ADF receiver on board, so all our NDB approaches are flown as GPS overlays. The sim though had an ADF so for IR renewals we did it raw data using HDG and V/S or FPA. But for 90 day recency we just flew the overlay.

[chimbu warrior]

Just to add a little to this discussion (and apologies for thread drift), why do CASA still insist on a DME endorsement, when DME can only be used to assist in an approach using another aid?

Does this still hark back to the days of DME homing and descent? That was the only instance where DME could be used as a stand-alone aid.

one wonders why CASA is inconsistent in their regulation of instrument rating tests especially as the CIR is not type specific.

It's just the kind of folks that they are......recently had an FOI tell me that that since I had changed types, I would need to do an I/R renewal in new type, even though I/R was not due for renewal. He insisted, but so did I. "show me that in the regs" I sez. Still waiting.

[Capn Bloggs]

Is this method a valid skill test of the pilot to fly an NDB approach using both vertical and lateral tracking via an FMS updated by a GPS?
CASA thinks so, or at least allows it.

My thoughts? No.

why do CASA still insist on a DME endorsement, when DME can only be used to assist in an approach using another aid?
Are you talking about the DGA qualification? I was discussing this with a colleague recently. We surmised that because you could only have NDB (not NDB-DME) on your licence, if you want to conduct a DME/GNSS Arrival (which requires an extra skillset) or NDB-DME, then you'd need a separate qualification demonstrating that you are able to fly down the steps/use the DME/GNSS to manage the vertical bit.

[A37575]

An autopilot or a coupled approach may be used in the demonstration of proficiency in instrument approach procedures.

I suggest the original term "coupled approach" was for coupled to an ILS. You can't couple to an NDB in the true sense of the word.

[BreakNeckSpeed]

I was of the understanding overlay approaches were not permitted in Australia (strictly speaking...):confused:

[topdrop]

I was of the understanding overlay approaches were not permitted in Australia
Permitted with CASA approval. Virgin 737s (not sure if it's both 700 & 800) recently approved to conduct approaches without use of ground based navaids.
I would think QFA 738s would be approved as well.

[porch monkey]

None of the new 800's even have ndb's anymore. Just fly overlays now...... Sure is painful trying to listen to the footy or cricket tho!

[Capn Bloggs]

Permitted with CASA approval. Virgin 737s (not sure if it's both 700 & 800) recently approved to conduct approaches without use of ground based navaids.
Pardon the French, but WTF is the benefit of being able to do overlay NDBs and VORs in Oz, where every runway likely to be used has at the least a proper GPS NPA?

[gunshy67]

Interesting replies.

The privileges of an instrument rating are not type sensitive. Therefore, doesn't the test need accommodate a test of all the aids that a pilots wishes to revalidate?

The skills required to fly automatics are quite different those required to hand-fly with or without the use flight directors or autopilot........and when considering operations that may be conducted by the pilot in the coming 12 months , isn't it necessary to be proficient in all skills?

The fact that there is no ADF's fitted to an aircraft is inconsequential. Simple fact ....you cannot be re-validated for an NDB in that aircraft if there is no ADF hardware fitted ....Have a look at CAO 20.18.

If CASA are allowing overlays or other such witchcraft without the necessary checks and balances for such approaches then so be it. They are the responsible authority if a future major untoward event occurs.

Finally, ETOPS/EDTO routes have been authorized in the past for adequate airports that are only equipped with an NDB. So should we have not have the skills and ADF equipment to fly such an operation.......... i.e. to validate the "pretty picture" with raw data?

OK. I have my tin hat on.

[blueloo]

Shouldn't the question be, why is any RPT JET allowed to conduct an approach on a 1930's era navigation aid which is subject to so many errors, when vastly better, safer approaches and navigation equipment is available?

[Trent 972]

Overlay Approaches Instruments
Qantas - CASA 64/12 (http://www.comlaw.gov.au/Details/F2012L00589) An aircraft operated by Qantas under I.F.R. may use an RNP-capable RNAV system in accordance with these instructions as a non-precision approach I.F.R. radio navigation aid for a published non-precision approach procedure, including a related missed approach procedure.
(2) This means that the FMC may be used as a substitute means of navigation, instead of a navigation aid, where the approach is in the approved navigation database, including where:
(a) a NOTAM states that the underlying navigation aid is out of service; or
(b) the onboard navigation aid is not serviceable or not installed.
(3) The procedure must not be flown if:
(a) the underlying navigation aid had been decommissioned; or
(b) the instrument approach for the navigation aid has been withdrawn.

Virgin - CASA 194/12 (http://www.comlaw.gov.au/Details/F2012L01560)In GNSS primary means of navigation, A330 and B737NG aircraft operated by Virgin Australia under I.F.R. may use an RNP-capable RNAV system in accordance with these instructions to conduct an FMS guided non-precision approach (NPA) using a published NPA procedure, including a related missed approach procedure.
(2) For GNSS primary means of navigation, the NPA for the operation must be available for use with the aircraft and contained in an approved navigation database.
(3) If subclause (2) is satisfied, the NPA can be flown without:
(a) the referenced ground based navigation aid being operational or geographically in position; or
(b) the airborne equipment for use in the NPA with the navigation aid being installed or serviceable


Civil Aviation Advisory Publication September 2012
DRAFT CAAP 178-1(2) (http://www.casa.gov.au/wcmswr/_assets/main/newrules/ops/download/draft-caap-178-1.pdf)
Can I fly an RNAV approach?
Yes. At present the only publically available RNAV instrument approach procedures available in Australia are based on GNSS. These procedures, sometimes referred to as a GPS/NPA, are identified on approach charts as RNAV(GNSS) approaches. Aircraft equipped with Technical
Standard Order C129a or other approved GNSS systems may conduct RNAV(GNSS) approaches. Not all aircraft fitted with GNSS (including FMC equipped aircraft) are approved for approach operations and pilots should determine the operational approvals applicable to each aircraft type.

Although many aircraft fitted with modern FMC systems have the capability to fly approach procedures using RNAV based on other than GNSS, including procedures based on conventional navigation aids, the use of RNAV in this respect is not approved in Australia.
An RNAV system may also be used to assist in flying a conventional approach. However, it is necessary for the navigation system upon which the procedure is based to be monitored (NDB, VOR etc.) to ensure that the obstacle clearance requirements of the approach are met, and that the procedure is flown within the tolerances of the navigation system on which the procedure is based.

[A37575]

Shouldn't the question be, why is any RPT JET allowed to conduct an approach on a 1930's era navigation aid which is subject to so many errors

How many accidents have happened in Australia caused by errors in the NDB? None that I have seen published. The fact is it takes a lot more skill to fly manually fly an NDB approach than it does to couple to an ILS for an autoland. But then the test is not about piloting skill anymore. It is a good bet that told to fly the simulator on a manually flown NDB approach raw data in a cross-wind most airline pilots used to button pushing LNAV and VNAV to "fly" the aircraft would fail their instrument rating test. Instead we have the ludicruous situation where the NDB part of the simulator test is ticked off as PASS when the whole shebang was done on autopilot and VAV and LNAV overlay. Talk about dumbing down of pilot standards. And CASA ccouldn't care less about the original principle as a test of a pilots flying ability on instruments, as long as a box is ticked and they get their fifty bucks or whatever for re-issueing the licence sheet.

I agree that the superb automation capability in airliners makes instrument approaches as safe as houses and a mere doddle for the button pushers, but to claim that the NDB approach on the Instrument Rating Test Form can be ticked off as completed successfully, is in my book, unprincipled. Feel free to disagree:ok:

[Oktas8]

I'm an airline pilot. With my colleagues, I fly raw data NDB approaches every three to six months in the simulator, in the cyclic (recurrency) program.

But would I do it in real life in IMC? Goodness me no, unless there was absolutely no choice. Why on earth would I use a 1930's era navigation aid of dubious accuracy? I would love to fly it in FMS mode, but my SOPs don't permit it.

That said, as a GA examiner I would not have allowed an NDB approach to be flown entirely on FMS & autopilot, and still ticked the "NDB approach competency" box on the form. Whether legal or not, it's a bit of an airmanship short cut! Airline examiners may well of course have a different take...

[First_Principal]

You can fly it upside down if you like AS LONG AS YOU MONITOR THE RAW DATA

Has anyone tried this, er, in the sim at least? :E

P.

[Capn Bloggs]

Has anyone tried this, er, in the sim at least?
I have been upside down in the sim "monitoring raw data" a few times. Wasn't doing an NDB though (at least I don't think I was...). :}

[Old Akro]

None of the new 800's even have ndb's anymore. Just fly overlays now...... Sure is painful trying to listen to the footy or cricket tho!

That's why you need the iPhone with internet radio!

[Roger Greendeck]

If your concern is about ensuring pilots have the skills to hand fly a raw data NDB approach then testing in a sim isn't realistic anyway. All the real world errors such as quanrantal and coastal effect are not simulated so you can get away without using the correct techniques.

[porch monkey]

Problem is akro, not much coverage at 38 odd thousand feet on the way to DPS.:sad:

[By George]

My previous Asian employer still required an NDB approach. We used Map and LNAV for the PNF and raw data for the PF, using centre Map with the ADF needles wandering about ( as they do). The local regulator is smart enough to appreciate that this is different to a Baron with a fixed card and now your Instrument rating up there is 'Type Specific'. Makes sense to me.

In ten years they will be gone to where the VAR went.

[Trevor the lover]

Flying NDBs upside down?

Reminds me of a flight on RAAF Pilots couse in the Macchi. Was doing a mutual with a course buddy - me in the back seat. We did a Pearce 260 departure - a pseudo SID where we just flew outbound on the 260 radial. He briefed he would do it inverted. Once on the intercept heading he rolled us upside down - was quite amusing watching him trying to sort out which way he had to shove the stick to roll onto the radial. actually, I think he did it better upside down than I could do it right way up!

[Tee Emm]

Trent 693. Many thanks for the info on CASA approved overlays. It sure opened my eyes. Makes the NDB approach a doddle to fly.:ok:
TM