737-700 Auto Land

[RDG41 1]

Hi,Recently I've been practicing my landing skills at KLAX runway 25L with autoland. My question is, when I follow the proper procedure of enabling the second auto pilot after capturing the glidescope, the PFD says that I have locked on to a channel 1 ILS signal. With both autopilots engaged shouldn't it be a two channel signal?Even though it states a 1 channel signal, I'm able to auto land with flare etc. I'm still learning here so it's possible that I'm just missing something. Thanks for the help,Ron

[basa 0]

Ron:Not only engage the second autopilot, you MUST tune the ILS freq. in both NAV1 and NAV2 radios for a full dual channel autoland.Jose Luis

[RDG41 1]

Yes, both nav radios were tuned to the ils freq. but the pdf was still displaying "CH 1" in yellow at the top. Does this mean I'm only tuned into one channel?

[basa 0]

But at a certain altitude (do not remember which one)the glideslope and the localizer indicators flash in yellow for some seconds and CH1 should change to CMD.Don't you get this sequence ?Jose Luis

[lostmoon 0]

I thought dual channel appears only when the ILS is CAT II/III enabled? Also you must tune both NAV radios to the ILS as suggested earlier and have both CMD engaged.Dunno.

[RDG41 1]

Yes, it does change to command and everything works fine for the auto land. I guess what I'm trying to find out is if it displays "CH 1" before going into CMD mode, what does this mean? I understand from what I have read that you can do an ILS landing with one autopilot (1 channel) which controls only 2 axis or with both auto pilots which was refered as "2 channels" for a full autoland. If I have both autopilots activated for a full autoland, should I be seeing "2 CH" in yellow on the pdf display or does it just display "CH 1" no matter if one or both autopilots are engaged?

[basa 0]

No, you will not see CH2.As I said, if both AP are engaged and both radios tuned you will see "CMD" in the PFD flight mode annunciator.That means "commanded" and means that you ARE already in dual channel.Jose Luis.

[zubart 5]

Single CH is displayed before CMD during a Dual channel autoland ILS. Single CH means that only one autopilot is engaged. It has nothing to do with 2 axis. The second autopilot will engage at about 1500 feet AGL after the ILS self test (flashing) on the PFD. Single CH will then change to CMD and FLARE will arm. The second autopilot must be engaged before 800 feet AGL. Refer to the FMA on the PFD to see what AFDS modes are active and armed. Referring to the MCP for active and armed modes can be deceptive.Floyd

[RDG41 1]

Thanks guys for all the clarification.It makes sense now.Cheers, Ron