Narrative:

I was acting as pilot in command and pilot flying of a flight to little rock where an incorrect DH set for a cat ii approach led to two missed approaches. While setting up the flight we checked the weather forecast for little rock which was 1/2 sm and VV002 at our time of arrival. During our preflight briefing; we discussed the weather and to expect the cat ii approach. We read through the QRH CAT ii checklist to familiarize ourselves with it and to review all the callouts. I then turned my attention back to the weather since the only CAT ii approach was to 22R; yet the winds were out of the northeast. Both the taf and metar were showing winds between 030 and 040 at 6-8 knots. Since this was a tailwind; I reviewed both the poh and fom to verify the limitations for a tailwind on a CAT ii. I determined that the winds were within limits. Once airborne in cruise flight; I returned to the fom to verify the visibility requirements since the d-atis in little rock was not reporting RVR. I sent an ACARS message to dispatch asking to send the current RVR; which was 6000 RVR. We continued to discuss the weather and again reviewed the wind and visibility requirements for the CAT ii approach; which we were still expecting. When about 30 minutes from landing; we received a new d-atis in which was reporting 030/7 1 SM VV003 and ILS approaches to 4L. Based on this ATIS; I elected to set up for the ILS 4L and briefed that approach. Just after briefing the approach; ATC gave us a descent from FL360 to cross 30 nm east of lit at 10;000. I set that up in the FMS and started the descent. The first officer then called the flight attendant's; sent the in-range and built the approach. About 20 minutes from landing; we were handed off to approach and checked in. We were given a vector and told to expect the ILS 22R. At the same time; we received an auto-update of the ATIS with was now reporting back down to 1/2sm and VV002. I then briefed the CAT ii for 22R. During the briefing; I stated that DH would be set to RA of 128. The first officer stated; that it should be set to 362. For a moment; I hesitated; saying; no; it should be 128. However; because I was tired; and despite knowing it should be 128; I then believed that I was wrong and the first officer was correct. We set the DH to [RA] 362 and continued the briefing and then ran the CAT ii descent checklist. Because of the error; we executed a missed approach and cleaned up the aircraft. I then did a quick fuel calculation for diversion fuel. We had about 8200 lbs on board and I calculated about 3000 lbs to divert to either of our 2 alternates. I then determined that we had enough fuel to make another attempt. We then reset the approach and double checked the course; frequency and altitude. At this time; still believing the DH set to 362 was correct; I did not change it when we reran the CAT ii descent checklist. We were given vectors for the ILS 22R and reconfigured for the approach in which we went missed again for the same reason. At this point I again checked out fuel; which was around 7;700lbs. I also realized that something was not right when an aircraft which was following us saw the runway and landed. I then realized that the DH set to 362 was in correct and that it should be 128. We verified this with the example on the descent checklist. We corrected the DH setting and I determined that we still had enough fuel to make one more attempt before having to divert. On this attempt; I saw the runway and landed with no further incident. There are several factors which led to this error. My attention was divided by the weather as well as being tired. Although we reviewed the CAT ii requirements; call outs; and approach plate prior to departing; I was fixated on the weather conditions. My major concern was if we were legal for the approach based on the winds and visibility. When we briefed the check list and call outs; we were focused on the weather and call outs; making sure we both knew what we were supposed to say; and did not discuss what the DH setting should be before we left. At the start of this flight; I was not feeling fatigue even though I had been awake for nearly 14 hours at that point. However; after being in the air for about a hour and half; I could feel fatigue starting to set in. When the time came to brief the CAT ii; I was getting very tired and when the first officer challenged me on the DH setting; my judgment was not clear. I did not trust my instinct which told me that I was correct and instead I believed the first officer. Since we had discussed the CAT ii several times; I believed that we had the DH set correctly and since we were getting close to the airport; I did not ask to double check the setting with the example in the checklist. In the future; I will make sure that the DH setting is briefed as per the example provided and double check the setting if there is any question as to the correct setting.

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Original NASA ASRS Text

Title: Air carrier Captain reported setting the incorrect decision altitude in the Radar Altimeter for a CAT II approach to LIT; resulting in two missed approaches. Fatigue was cited as a factor.

Narrative: I was acting as Pilot in Command and pilot flying of a flight to Little Rock where an incorrect DH set for a Cat II approach led to two missed approaches. While setting up the flight we checked the weather forecast for Little Rock which was 1/2 sm and VV002 at our time of arrival. During our preflight briefing; we discussed the weather and to expect the Cat II approach. We read through the QRH CAT II checklist to familiarize ourselves with it and to review all the callouts. I then turned my attention back to the weather since the only CAT II approach was to 22R; yet the winds were out of the Northeast. Both the TAF and METAR were showing winds between 030 and 040 at 6-8 knots. Since this was a tailwind; I reviewed both the POH and FOM to verify the limitations for a tailwind on a CAT II. I determined that the winds were within limits. Once airborne in cruise flight; I returned to the FOM to verify the visibility requirements since the D-ATIS in Little Rock was not reporting RVR. I sent an ACARS Message to dispatch asking to send the current RVR; which was 6000 RVR. We continued to discuss the weather and again reviewed the wind and visibility requirements for the CAT II approach; which we were still expecting. When about 30 minutes from landing; we received a new D-ATIS in which was reporting 030/7 1 SM VV003 and ILS Approaches to 4L. Based on this ATIS; I elected to set up for the ILS 4L and briefed that approach. Just after briefing the approach; ATC gave us a descent from FL360 to cross 30 nm east of LIT at 10;000. I set that up in the FMS and started the descent. The FO then called the FA's; sent the in-range and built the approach. About 20 minutes from landing; we were handed off to approach and checked in. We were given a vector and told to expect the ILS 22R. At the same time; we received an auto-update of the ATIS with was now reporting back down to 1/2sm and VV002. I then briefed the CAT II for 22R. During the briefing; I stated that DH would be set to RA of 128. The FO stated; that it should be set to 362. For a moment; I hesitated; saying; no; it should be 128. However; because I was tired; and despite knowing it should be 128; I then believed that I was wrong and the FO was correct. We set the DH to [RA] 362 and continued the briefing and then ran the CAT II descent Checklist. Because of the error; we executed a missed approach and cleaned up the aircraft. I then did a quick fuel calculation for diversion fuel. We had about 8200 lbs on board and I calculated about 3000 lbs to divert to either of our 2 alternates. I then determined that we had enough fuel to make another attempt. We then reset the approach and double checked the course; frequency and altitude. At this time; still believing the DH set to 362 was correct; I did not change it when we reran the CAT II descent checklist. We were given vectors for the ILS 22R and reconfigured for the approach in which we went missed again for the same reason. At this point I again checked out fuel; which was around 7;700lbs. I also realized that something was not right when an aircraft which was following us saw the runway and landed. I then realized that the DH set to 362 was in correct and that it should be 128. We verified this with the example on the descent checklist. We corrected the DH setting and I determined that we still had enough fuel to make one more attempt before having to divert. On this attempt; I saw the runway and landed with no further incident. There are several factors which led to this error. My attention was divided by the weather as well as being tired. Although we reviewed the CAT II requirements; call outs; and approach plate prior to departing; I was fixated on the weather conditions. My major concern was if we were legal for the approach based on the winds and visibility. When we briefed the check list and call outs; we were focused on the weather and call outs; making sure we both knew what we were supposed to say; and did not discuss what the DH setting should be before we left. At the start of this flight; I was not feeling fatigue even though I had been awake for nearly 14 hours at that point. However; after being in the air for about a hour and half; I could feel fatigue starting to set in. When the time came to brief the CAT II; I was getting very tired and when the FO challenged me on the DH setting; my judgment was not clear. I did not trust my instinct which told me that I was correct and instead I believed the FO. Since we had discussed the CAT II several times; I believed that we had the DH set correctly and since we were getting close to the airport; I did not ask to double check the setting with the example in the checklist. In the future; I will make sure that the DH setting is briefed as per the example provided and double check the setting if there is any question as to the correct setting.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.