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v1_rotate_v2
10th Apr 2006, 07:01
Dear all,

Don't you think this would save some fuel by flying a visual approach in lieu of executing an instrument approach in VMC conditions?

mairyhinge
10th Apr 2006, 09:24
The trouble is that modern day jets (airbus atleast) are not designed for "visual approaches". Why would I risk flying a visual approach with a high possibility to end up unstabilised when I can fly an IFR procedure and be garenteed terrain safe ?

VVJM265
10th Apr 2006, 09:55
Yes a visual is usually the most expidious way to get into an airfield. And you can still fly it as a stablized approach. If you don't like doing them, don't ever go into 26 at Albuquerque (KABQ), there is no instrument approach to 26!

http://www.naco.faa.gov/digital_tpp_search.asp?fldIdent=&fld_ident_type=FAA&fldCity=ALBUQUERQUE&fldAPName=&st=NM&fullName=New+Mexico&ver=0603&eff=03-16-2006&end=04-13-2006&btnSubmit=Complete+Search

http://www.naco.faa.gov/d-tpp/0603/00012I8.PDF

Elroy Jettson
10th Apr 2006, 11:46
Consider airline ops where the only visual approaches they do are in the simulator. One would argue that that conducting an instrument approach is the safer option. You only have to watch visual approaches flown by heavies into say Kansai onto runway 24 for about 30min to realise how little practice these guys get. As mentioned above, obstacle or terrain clearance calculated for you with a vertical profile or electronic slope guidance is safer than a visual approach. Remember some of these longhaulers do less than half a dozen landings a month.

Not sure that there would be any great fuel advantage in flying a visual approach vs runway aligned instrument approach. Also, atc/traffic delays dont allow you the flexibility to just do what you want.

Maybe the benefit you are refering to is for non precision non runway aligned approaches OCTA in VMC by IF pilots who arent training or updating their recency, or being checked, or improving their proficiency, or approaching an unfamiliar runway or flying a straight in approach... There are a few reasons why we do it. Hope this helps.

Shot Nancy
10th Apr 2006, 11:47
I knew I should have turned left @ Albuquerque.

cpdude
10th Apr 2006, 14:36
Dear all,
Don't you think this would save some fuel by flying a visual approach in lieu of executing an instrument approach in VMC conditions?


Short answer...yes!

Practical answer...won't work at a busy airport because aircraft would be diving in from all angles creating havoc. The Calvin& Hobbs arrival!:eek:

junior_man
10th Apr 2006, 23:51
Visuals work fine in LAX, SFO, and NY LGA plus many other airports. Depends on the airport and arrival setup as to whether it is beneficial.

cpdude
11th Apr 2006, 21:14
Visuals work fine in LAX, SFO, and NY LGA plus many other airports. Depends on the airport and arrival setup as to whether it is beneficial.

Ah yes...the US of A where you are cleared to land #7 and everything else is up to you!:eek:

tomuchwork
11th Apr 2006, 22:47
Hi,

I can just agree as well: of course a visual is fine, because

- you can save fuel
- save time
- be stabilized as well on a visual :confused: (as other guys mentioned, what are you doing if there is no instrument proc. available, diverting?????????)

But it is true, some airline pilots and as well some airlines don`t like visual procedures. I think this is not a good way to keep flying skills high(just on the sim is not enough!) - maybe the day will come where you will need as well this skills!

- AND FINALLY - a visual is great fun. And that`s why(at least me) we are doing this job.

7FF
12th Apr 2006, 01:23
Don't you think this would save some fuel by flying a visual approach in lieu of executing an instrument approach in VMC conditions

No. If the company were really trying to save fuel there are other ways that are less threatening. i.e. putting pressure on ATC/CAD to expedite arrivals and get rid of the ridiculous speed and height restraints into HKG and other airports. What is the point of doing a visual approach into LAX when ATC have vectored you half way across California. Visual approaches are good for ATC because they are then absolved of maintaining separation from other a/c. :hmm:

DOJETDRIVER
12th Apr 2006, 04:42
Ah yes...the US of A where you are cleared to land #7 and everything else is up to you!:eek:

If the JAR and the rest of the world is so superior, you wouldn't need a baby sitter to get you to the airport on a VMC day.

VVJM265
12th Apr 2006, 10:42
tomuchwork,


Yes visuals can be great fun! I used to fly the SA227 out of Naples (LIRN), and coming home from the south (feeder point from SOR) or west (feeder point ISKIA 23 NM to the west) with vectors ALLLL the way out to BENTO, was a perfect situation where a visual would save time. Because of the terain, the routing and approach would take you more than 40 miles out of your way (see approach link). ATC would sometimes clear us for the visual at 7000' at 1 or 2 miles abeam the runway after having told us repeatedly that the visual was unavailable. THAT was fun, and also a challenge to make it work out. Would be harder to do it in a big jet, for sure; but I saw A320s make it work often as well. You could still be stabilized by 500'-1000' AGL; and save yourself the 15 mins from going out to BENTO and back.



Fly safe!
265

LIRN ILS P RW24
https://164.214.2.62/products/digitalaero/terminals/v0603/europe_north_africa_middle_east/capodichino__lirn/ils_p_rwy_24.pdf

The definition below is from pg 15-21 of the Airplane Flying Handbook

http://www.faa.gov/library/manuals/aircraft/airplane_handbook/media/faa-h-8083-3a-6of7.pdf
THE STABILIZED APPROACH


The performance charts and the limitations contained in the FAA-approved Airplane Flight Manual are predicated on momentum values that result from programmed speeds and weights. Runway length limitations assume an exact 50-foot threshold height at an exact speed of 1.3 times Vso. That “window” is critical and is a prime reason for the stabilized approach. Performance figures also assume that once through the target threshold window, the airplane will touch down in a target touchdown zone approximately 1,000 feet down the runway, after which maximum stopping capability will be used. There are five basic elements to the stabilized approach.



• The airplane should be in the landing configuration early in the approach. The landing gear should be down, landing flaps selected, trim set, and fuel balanced. Ensuring that these tasks are completed will help keep the number of variables to a minimum during the final approach.

• The airplane should be on profile before descending below 1,000 feet. Configuration, trim, speed, and glidepath should be at or near the optimum parameters early in the approach to


avoid distractions and conflicts as the airplane nears the threshold window. An optimum
glidepath angle of 2.5° to 3° should be established and maintained.
• Indicated airspeed should be within 10 knots of the target airspeed. There are strong relationships between trim, speed, and power in most jet airplanes and it is important to stabilize the speed in order to minimize those other variables.
• The optimum descent rate should be 500 to 700 feet per minute.



The descent rate should not be allowed to exceed 1,000 feet per minute at any time during the approach.



• The engine speed should be at an r.p.m. that allows best response when and if a rapid power increase is needed. Every approach should be evaluated at 500 feet. In a typical jet airplane, this is approximately 1 minute from touchdown. If the approach is not stabilized at that height, a go-around should be initiated. (See figure 15-24 on the next page.)

Arrowhead
15th Apr 2006, 02:19
Well you do have Runway 16 at Macau which gives a bit of both - offset LOC/DME down to 900ish feet then a visual left turn onto the centeline at about 700ft (before you run into the bridge). Used when there is >10kt from the north.

Not quite so much fun though there are CBs on the approach, "few" below minima, and a screaming cross wind however...

You can see it here http://www.aacm.gov.mo/english/d_files/AIP/AIP_AD.PDF on page 72

QNH1013
17th Apr 2006, 14:31
Arrowhead,

Yeah, it's fun doing the RW16 landing once in a while especially with those nasty winds at times. But you guys must be experts at it since you'll get to do it more often than anyone. Having all the fun hand flying it in! :)

throw a dyce
18th Apr 2006, 07:51
When I was in ATC at HK,a visual approach was a real no-no.All approaches had to be ILS,or VOR/DME.
I could never understand why,as CLK is so easy to find.What was the problem with a visual to 07L/07R?
Where I am in the UK we use visual approaches all the time.You provide the a/c with IFR separation,or they become visual with the a/c ahead and you advise vortex spacing.
Mind you there were a lot of things about HK ATC that were puzzling.Must have been a Kai Tak hangover,but they did visuals there.:hmm:

Herc Jerk
19th Apr 2006, 08:03
Visual approach in HKG...?

What's the met abbrev. for 3ks vis in pollution?:hmm:

mairyhinge
19th Apr 2006, 09:00
Met Abbrev for 3k vis in Hong Kong is........ wait for it..... CAVOK !

BusyB
19th Apr 2006, 11:06
3K Vis into sun in HK you'll see the runway at 300'

throw a dyce
20th Apr 2006, 11:32
It's called 3000m in Haze:ok:
We can use visuals down to about 1000m RVR.If you get very low fog and gin clear round about,it's possible.
I agree that there is a lot of crap vis at CLK,but equally some days when you can see for miles.:cool:

bekolblockage
20th Apr 2006, 23:00
I agree that there is a lot of crap vis at CLK,but equally some days when you can see for miles.
Yeh throw a , almost all the way to Tung Chung! :D
Not too many of those days since you left.

sizematters
21st Apr 2006, 02:36
quite simply with traffic flow at most major airports doing a "Visual" makes Naff all difference ...................and with the ATC at CLK ?? by the time you've finished "Holding" or doing dog legs or vectors round half the south china sea, who cares???...............Now if they would let us just do our own thing using LNAV/VNAV with very little or no speed control we could actually save quite a bit of gas........

as for the vis at CLK ??

hey most days you can pick the runway out between 1000 and 500 feet on finals......................................