GPS/IRS based low visilbilty solutions?

[YakYak]

Following the LIN disaster, a thought has occurred that I'd like to encourage a discussion on.

Many modern and inexpensive cars these days have onboard GPS navigation equipment, with voice prompts for impending turns, and other directional guidance.
Since many transport aircraft have GPS or inertial navigation equipment, why not modify it to provide taxi assistance as a part of EFIS/EICAS perahps, in the same way?

A current database of world airports and associated taxiways is easilly achieved, and after landing or indeed before takeoff, the desired taxiing route could be entered by the crew, or perhaps linked to the equipment automatically from the ground (for the near future, perhaps?), thereby completely removing taxi confusion.

I think this would be a major aid for even familiar pilots at complex airports in all kinds of visibility, but the advantages in lowviz are obvious.

I'm tired of people pointing the finger of blame following dreadful accidents like at LIN. Lets combine our efforts and experience and do something POSITIVE about it.

Comments and suggestions please, fellow airline professionals? Over to you..........

[Konkordski]

NASA carried out tests of this concept under its LVLASO (low visibility landing and surface operations) programme using a 757.

Quite a bit of info on the NASA website about it which is here (http://www.nasa.gov). Enter LVLASO in the 'search' box.

[BigGreenPleasureMachine]

gps might be an option, but inav is far too inaccurate for the required precision. the possible prob with gps is that the a/c would have to transmit its position, thereby tying up a frequency which could be otherwise better used.

the fact that LIN didn't have an operational groound surveillance radar points to the fact that a change in technology isn't necessary, as these work reasonably well where they are installed. having said that, apparently JFK get primary targets on theirs when a truck goes past on the freeway.

i thought that thermal image cameras might be a good solution, and they'd give the benefit of being entirely autonomous. maybe someone with a bit more (operational) experience could suggest why this hasn't been explored?

regards,

BGPM.

[RATBOY]

Good old NASA... a political pork and public realtions machine with some science attached, some of it good and some of it doing masters thesiss over and over and over.

the technology exists to do what was recommended It will just cost a few $100K per aircraft and the surveys and mapping, I hate to tell you, are not sufficiently accurate or standardized to do this. Anyone have a spare few $10s of millions to devote to this? (.....silence,....crickets chirp.......)
Thought Not.

Okay. there are other ways around this with infrared that has been kicking around for years....that's what FLIR is on military aircraft to attack at night and in bad wx. Anyone have $250K per aircraft and some standards and procedures to use? Thought not.

Radar has been showing returns from stuff you didn't want to look at since Watson-Watt and before. Signal processing can get rid of a lot of it and in ATC primary returns are correlated with beacon returns. Problem here is with the target data update rate. It is too slow for modern airliners on the airport surface, on approach and takeoff/departure. thats where multilateration systems are coming in. Yes, military fire control radars have quicker update rates and you can tie them into the ultimate midair collision remediation capability...an AA missile...then you only lose one aircraft.

[ 01 November 2001: Message edited by: RATBOY ]

[ft]

It exists, is called ADS-B, is being implemented instead of completing the radar coverage above e g Russia and India and could have been in use already if "industry interests" (interests in other things than safety, of course) hadn't been delaying things. It's cheap, a lot cheaper than TCAS and operates using a TCP/IP-resembling protocol over the airwaves and DGPS.

Here is a picture (http://www.nyteknik.se/bilder/bildarkiv/arlandalans.gif) showing what it can look like when in use.

I've used it myself at my home PC, tracking test installations in aircraft and airport vehicles and it works great - to see a snowplow line during a winter storm at home in front of my computer with a cup of hot cocoa was a ballet-like experience.

I have also seen it on video when they tested it's ability to warn about and avoid runway incursions. When a vehicle entered the runway with an aircraft on final, the runway in the display flashed red and I think an aural alert was sounded. Would it have avoided the recent disaster in Linate and many other similar incidents? Undoubtedly.

As for tying up frequencies, it ties up only a few frequencies and they're outside of the normal airband. I don't know the specifics but the data transmission standard was laid down this spring at a conference in South America. If you want to look it up, it's called VDL mode 4.

Somehow, a lot of people still haven't heard about it. Amazing coincidence that it's getting very little publicity, don't you think?

Cheers,
/ft

[RATBOY]

ADS-B is very nice. It has been in use in one area of Alaska since January for ATC purposes. Unfortunately, it is not as straightforward as as you say. There are no internationally agreed protocols or operational specifications yet. VDL (VHF Data Link) Mode 4 is one data link proposed to do it, there are others. The data link in the Mode S specification (1090mhz) can do it and the link they use in Alaska can too...problem is it is also a piece of the radio frequencies used by military JTIDS data links.

It is also not a replacement for TCAS.

As far as cost goes the Alaska Capstone project bought 200 ship sets of GA avionics for I forget how many million dollars but I think it came out to $15 or $20K per airplane plus installation. This avionics fit isn't enough to do approaches and you need GPS local and wide area augmentation systems to get the navigation data to the point that you can do precision approaches.

It is a good thought though.

[ 01 November 2001: Message edited by: RATBOY ]

[BigGreenPleasureMachine]

what the hell is that, ft? swedish?

BGPM

[Dagger Dirk]

YAK YAK

Perhaps this low-tech system.

Click on http://www.iasa-intl.com/images/dreadle1.gif (http://www.iasa-intl.com/dreadle.html)

[ft]

BGPM, yes, it was invented by Håkan Lans from Sweden. Some links:

Standards, descriptions etc (http://www.nup.nu/)

The CARD project with lots of info (http://blinder.lfv.se/ans/card/)

GP&C Systems AB with more links (http://www.gpc.se/index.htm)

Have a good read. Cheers,
/ft

(Edited since UBB code does not like typos)

[ 05 November 2001: Message edited by: ft ]

[YakYak]

Dagger Dirk

Brilliant. Absolutely brilliant!

So simple.

To all the media hacks trawling these pages looking for tabloid fuel, why not show the world a possible solution to accidents like the one at LIN?

The public have a right to know. ;)

[PETERJ]

ft
Brilliant post .......many thanks for the links. Isn't SAS's involement ironic re Linate.

[YakYak]

TO ALL THOSE READING THIS - THIS IS THE REAL YAK YAK SPEAKING

Captain PPRuNe has helped me regain access to my username, after someone accessed my login and changed the password.

Whoever it is who STOLE my username and changed my password, you are an ar*ehole, and I have been recieving streams of questioning and angry emails from other PPRuNers about topics I know nothing about. Didn't you relaise that the email address on my profile would direct all communications back to me instead of to you?

If you want to post on this forum that's fine, but register your own username, with your own email address, instead of poaching mine.

I have CHANGED my password so you cannot do this any more.

To all those of you that have been offended by this moron, I apologise. From now on it's back to the Mil Pilots forum where I belong.

Regards

Yakkers