Cost Effectiveness of IFR GPS

[HEALY]

A bit of background,

Our company operates ME charter operations based in WA and are looking at the feasability (spelling???) of keeping the data card current on our TSO GPS installed in one of the acft. It is at the moment obviously only a cross check reference for NDB/VOR.Now for some questions and opinions

1) What are the operational benefits
2) Does it 'pay for itself' over say a 12 month period (no tedious holding patterns and procedures)
3) What is the cost to keep it current


Cheers

[Mainframe]

Healy

A GPS or DME Arrival (DGA) is usually the most cost effective and efficient instrument approach compared to NDB or VOR approach.

A GPS arrival will normally have a sector that aligns with your inbound track, or may be an omni directional approach.

It's simple, you just fly to the station and follow the steps down, usually to a comparable MDA as the NDB or VOR approach for that airport. You're right, No circling, no Holding, No outbound then inbound legs.

Some say it's a "Nancy" type of approach, not a real man's approach like a NDB. Yep, it's cheap and nasty and it works.

A VOR or NDB will take 10 to 15 minutes (0.2 / 0.3hrs @ the hrly cost of the aircraft). the GPS about the same as a visual approach.

Savings, probably $600 x 0.2 = $120 for typical NDB / VOR approach in extra flight time.


Cost of database updates:

option 1, get new card every month, about $1,000 pa. not good.

option 2, get a burner from Jepp, and a subscription, about $300 pa, plus the one off cost of a burner ("Skywriter") about $200.

once you own the burner, 2 or 3 GPS approaches (instead of 3 NDB approaches) a year will pay back the subscription. then it's money in the bank.

Contact Jepp in Melbourne. or visit their website.

extra bonus, you can fly RNAV in CTA with a current IFR database and usually can use GPS instead of DME for a lot of precision approaches.

[HEALY]

Cheers Mainframe

Its a strong case to put forward especially with the way GPS and Free Flight concept is developing.

[assymetric]

Hey HEALY,

Why not also do GPS NPA on a VMC day save money on a visual.
It would pay itself in less then a year.

[On eyre]

Another major benefit from having IFR GPS is the ability to conduct GPS NPA's which are (a) already very widely available in this country and more importantly (b) usually have a lower MDA than either a GPS/DME arrival or an NDB or VOR approach.
This operationally means you can often complete an approach to a landing when you might not be able to when the conditions are really crappy with consequent cost benefit. Worth every cent!!

[OzExpat]

Just don't buy a TSO-129a Receiver unless you get an iron-clad guarantee that it's upgradeable to TSO-146a standards. You'll find lots more advantages to TSO-146a compliance that will end up saving even more money in the future.

If you're using aircraft with FMS, you'll be looking for ompliance with TSO-145a instead of TSO-146a, which is stand-alone equipment. Not a lot of 146a gear on the market yet and, AFAIK, there won't be any 145a kit on the market for quite a while yet. Thus, you'll be buying equipment that complies with 129a and I understand that most of the latest generation stuff will be upgradeable to 146a, but always wise to check before purchase.

[Dale Harris]

We've been using them for the last three years or more. Wouldn't be without them. Ask any of our drivers, you'll get the same answer. Saves us money, time, fuel and increases aircraft availability in some circumstances for us. Not to mention they are generally a safer approach than an NDB or VOR.

[Dale Harris]

Generally a straight in approach, (Usually no circling), simple tracking, no procedure turns on the way in, damn sight easier to track accurately that some ****ty old NDB, what's not to make it safer???? I really think anything that makes a single pilot IFR operation easier and more accurately flown, especially in the approach phase has to be safer. You don't agree??

[Mr Whippy]

Healy, you will also get a benefit at night - it's much more efficient to fly a GPS arrival than a visual approach when your LSALT is significantly higher than circuit altitude.