Can we perform autoland with ils cat1 signal?
 

I'd ever heard that cat1 ils signal wasn't approved for autoland.

But in some authorities approved the runway with only ils cat1 for autoland

according to

1 no offset locallizer

2 glide path not steeper than 3.0 degree

3 have at least ils cat1 signal

4 runway slope not more than ....%

5 terrain 300 m before threshold is different from threshold elev not more

than ....ft somethings like that

etc.

so can we perform autoland with ils cat1 signal.

if we can't

how can we practice for currency simulated autoland in cat2/3 and for

aircraft airworthiness for autoland every 30 days eg.

would you please give me and answer?

What is this, 'CAT' 1/2/3 stand for?

An 'Autoland' is not the same thing as a Cat 2/3 approach. The aircrfat doesn't care whether visibility is good or bad, or whether the ILS is a CAT 1 or a CAT 3 installation, if you tell it to do an autoland, it will try and do one to the best of it's ability. It's ability to do so is affected by the exmaples of criteria you mention: G/S angle, no offset LLZ etc.

CAT 2/3 approaches don't use a 'special' kind of ILS system - it's the same bit of kit, just supplemented with runway lighting, back-up power, monitoring, an accurately surveyed approach, ATC LV Ops etc etc.

So as long as the technical requirements for a safe autoland are in place (and you mention a few of them) as defined by your regulator/company, you don't need a 'CAT 2/3' ILS to do one - if you are conducting the approach to CAT 1 minima (as you should be), there ought to be no problem letting the aircraft fly to touchdown, since you will have the necessary visual references to disconnect the autopilot and take control if you don't like what you see (just like when the FO's flying ;)).

Be sure to apply any other relevant procedures, such as performance corrections to LDR or GA WAT limit, which may be associated with autolands, though.

If in doubt, ask a company training captain.

In theory a good autopilot system will fly an autoland on a Cat 1 ILS. However, in practice beware of the quality of the beam – all UK Cat 1s were suitable, but I cannot vouch for any others – ask the flight checking department. Cat 1 ILS are unprotected from external disturbances and do not have failure backup systems. Thus training on ILSs within the constraints you that quote should be OK, but one of the biggest problems is the terrain profile in the undershoot, if this is not suitable, then the rad alt input it can give some very interesting arrivals which detract from the confidence in the system.
I doubt that ground roll-out will work satisfactorily.

With the Lockheed L1011, the only constraints are the following, besides those already listed...

There must be no limitations on the use of the glidepath below a certain height (which is normally printed on the approach chart), if there is, and...

The threshold crossing height must not be lower than 42 feet with the standard body model.

IF the TCH is lower than 42 feet, and an automatic approach/landing is attempted, the MLG to approach light clearance can be severy compromised.

Frangible approach light bits are just that, but you surely don't want to find out, the hard way.:uhoh:

NB.
The rollout function works just fine, in my experience, with the L10.

After all, the L1011 was designed from a clean sheet, with CATIII in mind, with no compromises.
None whatsoever.

A fine aeroplane!

:ugh:


yawn......

Yes you can !

Once the weather minima get worst (below CAT I min.) then it become illegal ! Right ??

Most of it's been said but remember that if you are intending an autoland on a Cat I ILS (or even Cat 2/3 when LVP are NOT in force) that objects such as aircraft and vehicles etc may well be manoeuvring and affecting the integrity of the ILS which may cause an autopilot disconnect at an embarassing time!

I recall doing a practice autoland years ago on the B737-300 on a Cat 3 ILS when LVPs were NOT in force when the autopilot disconnected after the nose up trim had been applied by the automatics at 400 ft and having to do some pretty rapid retrimming and correction of the approach to ensure a safe landing. The oscillation on the localiser had been caused by an aircraft that had departed and overflown the localiser transmitter when we were on short final.

In summmary, by all means autoland off a non-protected ILS but exercise caution!

As previously stated the autoland works with any ILS no matter what category. Interference from taxiing aircraft, etc is not protected. One day landing with smoke in cockpit on a B757 I coupled up as an autoland on a Cat 1 just as insurance in case the situation deteriorated during the approach so the plane would land and stop itself. Once we knew it wasn't needed we shut it off. Why not use every tool available in case TTTS.

Hello all,

Teung, Of course the airplane can do it !

The danger comes from the ground : LVPs (Low Visibility Procedures) HAVE to be in effect in order to free the ILS signal from any parasites that may deviate it : for example, the Runway Hold short positions are different when LVPs are in progress (further away from the runway, you've seen those cat II/III stop signs right ?) so that waiting aircrafts don't interfere with your signal in the last 100 feet.

so in case of emergency, if you want to do an autoland make sure the tower knows about it ! (there might be a whole lotta fire trucks and ambulances waiting for you there, well intentionned but DISRUPTING YOUR ILS SIGNAL ! !)

cheers

You can but As long as CAT1 IS NOT display on your FMA.
If CAT1 is display on the FMA you are not allowed to do an autoland. (well at least for airbus).

toung, it all comes down to what aircraft your are flying!
Check your AFM and you might find things such as "AP coupled landing compliance has been demonstrated with CAT II and CAT III performance quality beams only" or similar. It means the manufacturer places a restriction on the ILS beam quality to perform an autoland, disregarding the actual met conditions.
On top, any simulated (actually only the CAT II or III is simulated...) autoland performed ouside LOVIS procedures takes place on unprotected ILS signals and might be subject to disturbance(s).

Hope this helps :cool:

The ILS system is a method of "feeling" your way to the runway - this was shortened to "feline" by the US pilots, and hence "CAT".

But to be honest it is short for CATegory

Unless further restricted by your company documents (FOM/AOM, FHB/AFM), the 747 series (200/300/400 at least) are certified to autoland when coupled to any approved/certified ILS. It makes sense to alert Approach and/or Tower that you will autoland, so they can protect the ILS intrusion zones on the taxiways. If you don't, you may get undesirable excursions.

Generally 2 or 3 functioning and connected autopilots are required for a full autoland, just as they are required for Cat 2 and Cat 3 approaches.

So, to practice a Cat 2 or Cat 3 approach/landing, you can do it in any weather, as long as you meet the requirements and notify Approach/Tower.

Thanks veryyyyyyyyy much for every comments.

I've got many ideas from all of you and my eyes were opened.(cavok:} )

Thanks again.

Boeing 717 autolands quite nicely with CAT 1 (which is all we have in Australia). Right on the money and nicer touchdown than many 717 pilots can manage.

Just make sure the ILS critical area (as we call it here) is protected.

Is this from the A320 Series FCOM any use to you?
''AUTOMATIC LANDING IN CAT I OR BETTER WEATHER CONDITIONS
The automatic landing system's performance has been demonstrated on runways equipped with CAT II or CAT III ILS/MLS approaches. However, automatic landing in CAT I or better weather conditions is possible on CAT I ground installations, or when ILS sensitive areas are not protected, if the following precautions are taken :
The airline has checked that the ILS/MLS beam quality and the effect of terrain profile before the runway have no adverse effect on AP/FD guidance. In particular, the effect of terrain discontinuities within 300 meters before runway threshold must be evaluated.
The crew is aware that LOC or GS beam fluctuations, independent of the aircraft systems, may occur and the PF is prepared to immediately disconnect the AP and take appropriate action, should unsatisfactory guidance occur.
At least CAT2 capability is displayed on the FMA and CAT II/III procedures are used.
Visual references are obtained at an altitude appropriate to the performed CAT I approach, otherwise go–around is initiated.
When the crew does not intend to perform an autoland, they should disconnect the AP at or above 80 feet : this altitude being the minimum to take over and feel comfortable.
Nevertheless, for safety purposes, the AP may be disconnected at anytime.''
Cheers all,
mcdhu

In the UK, if you tell the TWR that you will be doing a practice autoland you are likely to simply be told that the ILS Sensitive Area is not protected. It is usually just not possible or practical to provide the protection that is required to support an actual CATII/III approach for a single aircraft in good wx.

In that case, be alert for excursions, and go manual if something unusual happens. Not a big deal in VMC!

Not that l am condoning the use of autoland off a CAT 1 ILS, however if you are on the 777 most LLZ interferances are "ironed out" by the autopilot using the GPS signal as a back up.

As such it will do a good job in almost all situations. Probably even better than the geriatric L1011. :}

halas