IREX Question
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IREX Question
G'day everyone!This one has me stumped. If anyone could shed some light on the subject that would be great! Flight details: IFR CHTR by night conducted in VH-OZY You wish to change to NGT VFR procedures over the last route segment. No operational requirements imposed by lighting or weather. No alternate is available for this flight. The minimum number and type of serviceable navigation aids required at the destination for this flight are:a) A VOR or NDB is required b) No aids are required I put b) as my answer as VH-OZY is equipped with '1 x GPS Certified to TSO-C129[a] for IFR operations, but it was incorrect...AIP ENR 1.1 73.3.3.b states that you do not need to provide an alternate if the aircraft is fitted with an approved GNSS receiver, and both GEN 1.5 section 2 and 8 state that the C129 is approved for this purpose. Any help is appreciated!
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Jepps say that for Night VFR, ADF, VOR or GPS, and the conditions are...
Note 3: In this table GPS refers to GNSS equipment certified to TSO-129, C129a, C145a, C146a or equivalent certified by CASA.
Note 3: In this table GPS refers to GNSS equipment certified to TSO-129, C129a, C145a, C146a or equivalent certified by CASA.
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G'day, I'm new to the wonderful world of IFR so pardon the ignorance...
Where is the question from? Is it from a school? a book? IREX test? Also what qualifications do you as the flight crew require to use the GPS?
From what I'm reading in the AIP, it sounds like you need a VOR or NDB ( answer A) - unless you are qualified to use the GPS (then answer B). Since B is wrong, I'm guessing it's a question from a school/Instructor? and you don't have appropriate quals. to use the GPS??
Where is the question from? Is it from a school? a book? IREX test? Also what qualifications do you as the flight crew require to use the GPS?
From what I'm reading in the AIP, it sounds like you need a VOR or NDB ( answer A) - unless you are qualified to use the GPS (then answer B). Since B is wrong, I'm guessing it's a question from a school/Instructor? and you don't have appropriate quals. to use the GPS??
Last edited by elche; 17th Aug 2008 at 05:03.
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whaet... you were correct with all your referances. but you missed one more page to do with nav aid requirements. That is the Enroute navigation system requirement found in:
Jeps ATC-General Flight Procedures-para5.11 (sorry dont no the AIP ref)
That says in the table that for CHTR/AWK 5700 or less you require one of the following....ADF,VOR, or GPS(TSO 145a or 156a)
Spikey21... you were right but those reqmts are for Night VFR(not chtr or AWK...so being private)
PS whaet... if your doing your IREX then I used the Airservices docs as i was resistant to changing from airservices as thats what i had learned on, but I have now got Jepps. I think they are the best thing ever invented and put airservices to shame. I would need a suitcase to carry around all the airservices docs. But with jepps I have everything in 1 file. And the layout of everything makes more sense. There is a reason why airlines use them. The only people you will find that talk them down is the ones that havnt tried them.
Jeps ATC-General Flight Procedures-para5.11 (sorry dont no the AIP ref)
That says in the table that for CHTR/AWK 5700 or less you require one of the following....ADF,VOR, or GPS(TSO 145a or 156a)
Spikey21... you were right but those reqmts are for Night VFR(not chtr or AWK...so being private)
PS whaet... if your doing your IREX then I used the Airservices docs as i was resistant to changing from airservices as thats what i had learned on, but I have now got Jepps. I think they are the best thing ever invented and put airservices to shame. I would need a suitcase to carry around all the airservices docs. But with jepps I have everything in 1 file. And the layout of everything makes more sense. There is a reason why airlines use them. The only people you will find that talk them down is the ones that havnt tried them.
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whaet......It is now some years since I did the IREX exam but I see from the example you have posted that the tricks have not changed. I have never come across an exam that was so designed to mislead the student and therefore every question must be read very, very carefully.
In the question you have posted it would appear on first reading that it is looking for the minimum requirements for NVMC, however, the flight was a CHTR flight before the downgrade to NVMC and therefore it is those requirements that are the minimum, as brns2 has said.
The tricks in IREX are many and varied, the questions are designed to mislead. Good luck with them.
In the question you have posted it would appear on first reading that it is looking for the minimum requirements for NVMC, however, the flight was a CHTR flight before the downgrade to NVMC and therefore it is those requirements that are the minimum, as brns2 has said.
The tricks in IREX are many and varied, the questions are designed to mislead. Good luck with them.
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Your answer is correct. They got it wrong. That is the point of downgrading to night VFR. In those Q's you can assume you are certified to use the aid if it is in the A/C unless stated otherwise.
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I just found this exact same question in the Bob Tait Cyberexam IREX-1. There is no mention of a GPS in this question, so I still believe this must have been a question from an Instructor trying to trick his student... 
Would love to know where he was asked this question. Bob Tait uses VH-OZY in most of his questions, and in the real world VH-OZY is C172 in rockhampton.
Does ASA use VH-OZY too??
Would love to know where he was asked this question. Bob Tait uses VH-OZY in most of his questions, and in the real world VH-OZY is C172 in rockhampton.
Does ASA use VH-OZY too??
Last edited by elche; 21st Aug 2008 at 22:49.
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brns2 is correct. No trick question - just real life.
TSO 145a or 156a is for sole means navigation = no alternate or other navaids required.
TSO C129 / C129a requires either an alternate or other navaids = no go.
A NGT VFR destination without a navaid requires an alternate within 1 hour flighttime with other navaids. No alternate = no go.
IFR or NGT VFR, the flight can only be done with a TSO 145a or 156a GNNS.
TSO 145a or 156a is for sole means navigation = no alternate or other navaids required.
TSO C129 / C129a requires either an alternate or other navaids = no go.
A NGT VFR destination without a navaid requires an alternate within 1 hour flighttime with other navaids. No alternate = no go.
IFR or NGT VFR, the flight can only be done with a TSO 145a or 156a GNNS.
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No, TSO-C129 is fine for NVFR, an alternate is not required.
Refer to the table in GEN 1.5 para 2.1. It shows that for NVFR, 1 system is required, and the specified system types are ADF, VOR or GPS. The condition is to refer to Note 3.
Note3: In this table GPS refers to GNSS equipment certified TSO-C129, C129a, C145a, C146a or equivalent as determined by CASA.
Also check ENR 1.1 para 73.3.3 which basically says that NVFR requires an alternate within one hour unless the destination is served by one radio naviagation aid (NDB/VOR) and the aircraft is fitted with the appropriate radio navigation system capable or using the aid, or the aircraft is fitted with an approved GNSS receiver, and the pilot and aircraft meet the requirements of GEN 1.5 Section 8.
So then checking GEN 1.5 para 8.5.4.2 it basically says that the GNSS receiver must be certified to meet TSO-C129, C129a, C145, C145a, C146, C146a or equivalent approved by CASA. This is followed by a table that shows this also.
Read the references in full if you don't trust my summary, you'll need to know these bits if you're doing IREX anyway.
Hopefully this clears things up once and for all!
Refer to the table in GEN 1.5 para 2.1. It shows that for NVFR, 1 system is required, and the specified system types are ADF, VOR or GPS. The condition is to refer to Note 3.
Note3: In this table GPS refers to GNSS equipment certified TSO-C129, C129a, C145a, C146a or equivalent as determined by CASA.
Also check ENR 1.1 para 73.3.3 which basically says that NVFR requires an alternate within one hour unless the destination is served by one radio naviagation aid (NDB/VOR) and the aircraft is fitted with the appropriate radio navigation system capable or using the aid, or the aircraft is fitted with an approved GNSS receiver, and the pilot and aircraft meet the requirements of GEN 1.5 Section 8.
So then checking GEN 1.5 para 8.5.4.2 it basically says that the GNSS receiver must be certified to meet TSO-C129, C129a, C145, C145a, C146, C146a or equivalent approved by CASA. This is followed by a table that shows this also.
Read the references in full if you don't trust my summary, you'll need to know these bits if you're doing IREX anyway.
Hopefully this clears things up once and for all!
Last edited by QF2; 22nd Aug 2008 at 13:09. Reason: Spelling
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QF2,
As always I stand to be corrected but I believe the question revolves around the higher requirements for CHTR, the downgrading to NVFR is a furphy. The answer has nothing to do with the requirements for NVFR as the flight is still a charter flight.
Therefore in answering the question you have to decide what navigation aids are required so that the charter flight can be conducted to an airfield without an alternative being required with at least one of the sectors being flown under IFR.
As always I stand to be corrected but I believe the question revolves around the higher requirements for CHTR, the downgrading to NVFR is a furphy. The answer has nothing to do with the requirements for NVFR as the flight is still a charter flight.
Therefore in answering the question you have to decide what navigation aids are required so that the charter flight can be conducted to an airfield without an alternative being required with at least one of the sectors being flown under IFR.
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Yeh this is all difficult as our interpretations of the table vary.
When I look at the table in GEN 1.5 Section 2.1, the different types of operation are specified. You're going by the type of operation specified as CHTR/AWK 5,700KG or less MTOW. I've been going by the type of operation specified as NGT VFR. Unfortunately, neither of them refer to the other category, ie. the reqs for charter don't have any reference to NVFR, and the reqs for NVFR don't have any reference to charter. As the flight was being conducted NVFR, I believe the type of operation would be NGT VFR from the table, and believe that this covers private, airwork and charter. However, looking from your perspective, the charter type of operation could be seen to include ALL charter.
All this is exactly what the thread topic is about, but short of finding any other references, it is very difficult to interpret what type of operation the flight should be specified as. I guess it's no different to half the other rules where there doesn't appear to be any definitive answer, I think we need a lawyer!
EDIT: Have since hunted down a question. Basically, it was an IFR charter flight becoming NVFR for the last route segment. It said the aerodrome was only served by an NDB, and only said the aircraft had one ADF. No reference to GPS, or as to whether the flight would be CTA or OCTA. It asked if an alternate was required, and the answer was that no alternate was required.
The NGT VFR type of operation in the table works for this as only one nav system is required. Charter could use one nav system as well, but only for OCTA, as two nav are required in CTA.
When I look at the table in GEN 1.5 Section 2.1, the different types of operation are specified. You're going by the type of operation specified as CHTR/AWK 5,700KG or less MTOW. I've been going by the type of operation specified as NGT VFR. Unfortunately, neither of them refer to the other category, ie. the reqs for charter don't have any reference to NVFR, and the reqs for NVFR don't have any reference to charter. As the flight was being conducted NVFR, I believe the type of operation would be NGT VFR from the table, and believe that this covers private, airwork and charter. However, looking from your perspective, the charter type of operation could be seen to include ALL charter.
All this is exactly what the thread topic is about, but short of finding any other references, it is very difficult to interpret what type of operation the flight should be specified as. I guess it's no different to half the other rules where there doesn't appear to be any definitive answer, I think we need a lawyer!
EDIT: Have since hunted down a question. Basically, it was an IFR charter flight becoming NVFR for the last route segment. It said the aerodrome was only served by an NDB, and only said the aircraft had one ADF. No reference to GPS, or as to whether the flight would be CTA or OCTA. It asked if an alternate was required, and the answer was that no alternate was required.
The NGT VFR type of operation in the table works for this as only one nav system is required. Charter could use one nav system as well, but only for OCTA, as two nav are required in CTA.
Last edited by QF2; 23rd Aug 2008 at 14:00.
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Alternate requirements vs minimum for flight
I believe this question is about alternate requirements, not the minimum number of aids req'd to be fitted to the A/C. These are two seperate issues. CHTR day or night will have the same requirements under the IFR. (Gen 1.5 - 2.) The question doesn't mention CTA or OCTA so this can't be answered. CHTR NVFR only requires 1 aid to be fitted to the A/C. This is not what is required at the AD. This is a question about alternate requirements. (ENR 1.1 73.3). A flight permitted to operate under the NVFR ie CHTR may use TSO - 129 GPS to meet the alternate requirements and therefor not need an aid to service the AD.
The A/C will need to be fitted with the aids to meet GEN 1.5 for IFR CHTR as this can have higher requirements, but the AD doesn't need to be serviced by a ground based aid if the A/C is fitted with a serviceable 129 or above GPS and the pilot is qualified to use it. The answer to the question is no alternate required. The advantage of downgrading to NVFR is to reduce the alternate requirements.
Hopefully this helps
The A/C will need to be fitted with the aids to meet GEN 1.5 for IFR CHTR as this can have higher requirements, but the AD doesn't need to be serviced by a ground based aid if the A/C is fitted with a serviceable 129 or above GPS and the pilot is qualified to use it. The answer to the question is no alternate required. The advantage of downgrading to NVFR is to reduce the alternate requirements.
Hopefully this helps
