How is the laser on the King Air used to check and calibrate the ILS system for a runway or it's lighting system? (I'm assuming it's the approach lighting & rwy threshold & touchdown zone lighting that's being checked).
When I think of a laser, I think of a laser beam that's aimed at something.
In the case of an ILS system being calibrated, what would the laser beam be pointed at? Is there a ground crew involved in the test that has equipment set up in the middle of the runway's touchdown zone that the aircraft's laser is aimed at while on the proper glideslope angle ....... perhaps?
Mr Spaceman From Canada, joined Mar 2001, 2786 posts, RR: 9 Reply 2, posted (9 years 5 months 2 weeks 6 days 23 hours ago) and read 1426 times:
Hello Contact tower.
Thank You, for your reply.
OK, so the white object on the aircraft's belly isn't a laser, it's actually a reflector for a laser that's positioned on the ground beside a runway's touchdown zone by a crew of technicians.
The caption under the photo with the guy crawling under the King Air says he was under there to "clean the laser" so I guess the photographer had the right idea ........... but just not perfect info. But then, who's perfect?
I understand that it's only the PAPI & VASIS lights that are tested (I don't remember what PLASI stands for), and not the approach lights. That makes more sense.
I appreciate your explanation of how an airborne reflector and ground based laser are set up to perform these calibrations. I understand that the exact details of these tests would be a bit to much to go into detail about.
QantasA332 From Australia, joined Dec 2003, 1500 posts, RR: 34 Reply 3, posted (9 years 5 months 2 weeks 6 days 20 hours ago) and read 1388 times:
The laser reflector is referred to colloquially as the 'brick,' and it consists of a number or prisms which give the ground-based laser something to lock onto. While the aircraft's GPS can give the position of the aircraft to within 8 feet, something more accurate is needed -- hence the ground-based laser, which calculates the plane's location to within about 6 inches. That position is compared to the position of the glideslope and localizer, which is then used for various calibrations.
If you have access to it, the January 2003 issue of Air International has an extensive, very interesting article on Flight Precision Ltd. (the company using that system) and their work.
Mr Spaceman From Canada, joined Mar 2001, 2786 posts, RR: 9 Reply 4, posted (9 years 5 months 2 weeks 6 days 15 hours ago) and read 1334 times:
>> QantasA332, Thank You Sir, for yor reply and excellent info.
You are obviously a very smart guy, and I enjoy learning from you. You definetly have a bright future ahead of you!
I used to read the Air International magazine all the time (and have a lot of issues in boxes), but I've run out of time on my daily clock to read everything that I wish I could.
It's amazing just how precise these tests can be, but then again, CAT IIIa ILS (or CAT II & CAT I) approaches need to be fine tuned for a safe landing to be capable.
I've seen a Challenger 601 bizjet like this one (with low vis markings) from NAV CANADA shooting many approaches to different runways at Toronto's Pearson International (YYZ). I wonder if that jet has extendable laser reflectors ("bricks")?
Mr Spaceman From Canada, joined Mar 2001, 2786 posts, RR: 9 Reply 6, posted (9 years 5 months 2 weeks 6 days 2 hours ago) and read 1280 times:
You're very welcome.
Trust me, a smart young man like yourself deserves a good pat on the back. It's a pleasure to know that guys like you are out there. Us older men who have more grey hair on our skulls then colour are always happy to know that there are pro's growing up in this world of airplanes.
Regarding the Canadian NAV CAN Challenger jet, I remember listening to my receiver back in the winter and hearing a NAV CAN pilot (who knows what type of aircraft), who was shooting approaches to Toronto's YYZ, and at one point during the communications between the pilot and Toronto ATC the pilot became very upset with the controller and transmited these kind of words ...........
"Toronto center, let me explain to you that I'm in control, tell your friends, tell your boss. "I" will let you know what heading, altitude and airspeed I need to fly on. I'm currently over WASSIE at four thousand three hundred feet on course to intercept the ILS for 23. Do you copy?"
I was shocked to hear this pilot talk to Toronto ATC this way, I thought it sounded rather rude, however, I don't know what the deal is when a specially equiped aircraft that's owned by the government is flying test approaches.
Maybe the ATC controllers are supposed to be well aware of their (the pilot's), activities and need to vector other aircraft away from the test aircraft.
I just know that I've never heard a pilot be so stern with a controller before. It caused an uncomfortable feeling for me (as a listener), but, I also understand that somebody needs to put their foot down and explain who's in charge when it's nessesary.
QantasA332 From Australia, joined Dec 2003, 1500 posts, RR: 34 Reply 7, posted (9 years 5 months 2 weeks 5 days 21 hours ago) and read 1249 times:
Hmm, it does sound rather rude. I suppose when you're doing that sort of "important" work it can get to you, in a way. Still, that shouldn't really be necessary. Flight Precision Ltd.'s work it apparently hassle-free traffic-wise -- that is, they slot their approaches in among the regular traffic. So, depending on what exactly Nav Canada is doing, keeping traffic well away shouldn't be that much of a problem. Hmm...