Are B757/B767 ILS landings only performed by auto-pilot or also manually?
Regarding air shows:
Are accurate manual B757/B767 near-airport approaches and landings (when runway is visible) performed without airport based navigation signals?
Can a consistent glidepath (10 miles distant for example) be established for a runway touchdown without ILS or other nav-aid or would constant adjustments become necessary?
Can B757s/B767s be manually centered properly over a runway without difficulty, without ILS guidance? (Air show fly-bys for example) Would excess speed increase the level of difficulty?
(If these questions seem "dumb", it's only because I am.)
I have been flying the B767 now for around 6 years. You asked the following questions, so here goes with the answers. By the way there are no 'dumb' questions, maybe dumb people who don't ask the questions they'd like to.
"Are B757/B767 ILS landings only performed by auto-pilot or also manually?"
ILS approaches can be either flown manually or coupled to an ILS through the autopilot. The landing off a coupled approach can be either an autoland or a manual landing. The landng from a manually flown approach is always hand flown.
"Regarding air shows: Are accurate manual B757/B767 near-airport approaches and landings (when runway is visible) performed without airport based navigation signals?"
It is just as easy in B767, as in any other aeroplane, to visually fly an approach without the assistance of radio navigation aids. The radio aids are essential in bad weather though.
"Can a consistent glidepath (10 miles distant for example) be established for a runway touchdown without ILS or other nav-aid or would constant adjustments become necessary?"
Yes, you use a distance to run to touchdown versus altitude chart to fly the correct approach path, or Mark I eyeball it. Standard configuration and rate of descent helps as well as visual lighting approach path aids on the airfield itself.
"Can B757s/B767s be manually centered properly over a runway without difficulty, without ILS guidance? (Air show fly-bys for example) Would excess speed increase the level of difficulty?"
Yes, easy to do, look out the window and manouvre appropriately. Excess or high speed just means that you have to anticipate your manouvring requirements.
I hope these answers are what you wanted.
Regards, BH.
Last edited by Bullethead : 24th August 2008 at 12:54.
By the way, a couple of other questions regarding B767 navigation:
- Are flight routes or flight plans comprised of a series of waypoints? Are such waypoints presently comprised of GPS (WAAS) data or other conventional nav-aid information? (VOR, MLS, etc)
- Does B767 auto-pilot operation have built-in speed limitations when flying at certain minimum altitudes? (Restriction of high speeds at low altitudes that might be deemed dangerous.)
By the way, a couple of other questions regarding B767 navigation:
Yeah, I've got time for a few more questions,
"- Are flight routes or flight plans comprised of a series of waypoints? Are such waypoints presently comprised of GPS (WAAS) data or other conventional nav-aid information? (VOR, MLS, etc)"
Flight plans are constructed using both named Lat/Long waypoints and radio nav beacons. Generally loaded from the FMC data base. Around here, Oz, there are not that many radio aids so named Lat/long waypoints are more prevalent. In the USA or Europe things would be different due to the prevalence of navaids. The waypoints can be used by GPS, MLS etc
"- Does B767 auto-pilot operation have built-in speed limitations when flying at certain minimum altitudes? (Restriction of high speeds at low altitudes that might be deemed dangerous.)"
Depending on the operating mode the autopilot protects from overspeed, underspeed and also landing gear and flap limit speeds. If there is a speed restriction which is slower than the aircraft maximum then it's up to the pilot monitor it and not exceed it.
I noticed that Rockwell-Collins MMRs and Honeywell FMCs capable of using GPS signals were planned for use in B757s and B767s during the late 1990s and I thought with WAAS in use in North America that waypoints would be largely GPS based.
Besides the FMC database, from where else would waypoint-based flight paths be obtained?
Waypoints are waypoints, and can be used by any nav computer. A GPS is not a nav computer as such, it is a sophisticated radio receiver with a built in nav computer. Any waypoint can be used by any nav computer as long it is stored in the database. There are really no GPS specific waypoints.
Some of the B767s I fly have a GPS position update capability which is used by the FMC to refine the accuracy of the raw IRS position, some don't and rely on radio navaid position, RNAV, updates.
Waypoint information come from a database, or be transmitted to an aircraft by ACARS or be manually inserted by using Lat/Longs.
WAAS is a ground based GPS supplemental system to give better coverage and further refine the satellite GPS data for use in particular terminal areas.
Once transmitted by the ACARS, does waypoint flight plan information need to be implemented by the pilot or can an already engaged auto-pilot immediately utilize new information transmitted by ACARS?
Does auto-pilot operation need to be manually activated by a pilot or can instructions stored in the FMC cause an auto-pilot operation to engage automatically?
What ground party actually transmits the ACARS information?
However, by telling the FMC what you want it to do (before the flight), you can engage VNAV and LNAV (auto pilot modes) and in theory let it do it's own thing - In reality you rarely follow the FMC plan exactly so there will be some airborne adjustments to be made - OK, I am using the 733/5 as a benchmark here but assume the 75/6 doesnt require a whole lot of MCP (authopilot mode control panel) input either.
I have read that ACARS is not entirely secure. It seems unwise for there to be a system that could allow an unauthorized user to transmit false flight plan data directly to an aircraft's FMC.
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