B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 7815; Flight Crew Type 5763
Situational Awareness
Aircraft Equipment Problem Less Severe
General Maintenance Action
Aircraft; Human Factors
We were flying a visual approach. I was the PF; and we were configuring normally for a visual approach. I called for flaps 25; was pausing to call flaps 30 and noticed the LE FLAPS TRANSIT (amber) light illuminated. We looked overhead and noticed the #1 LE Slat was not indicating extended. The Captain looked out and saw it actually was extended. We had a short conversation and decided the safest course of action was to land as we were confident of our configuration of gear down; flaps 25; and all leading edges extended. The landing was uneventful; and we debriefed our experience as we waited for maintenance to defer the LE indication for our return flight.
We were on base to final. We received a master caution for the right side window heat. I turned off the heat and reset it; but the overheat came back. I decided to continue the approach. Prior to the FAF; at 170 kts flaps 5; the gear down; flaps 15; landing checklist was called. I began to run the checklist and flaps 25 was called for and selected. I noticed the MCP speed window was flashing and the aircraft was not slowing down. We noticed the LE transit flaps amber light was illuminated. We looked up to the overhead and noticed the number 1 slat was not illuminated. The aircraft was not slowing down. We decided to select 15 and try to reset the problem. The same error occurred and I looked outside and I could see the number 1 slat was fully extended as commanded. We decided to continue as the runway was in sight. Flaps 30 was called. The trailing edge flaps remained at 25 with the handle in 30. I believe the speed was still around 170. I reset the FMC to flaps 15 target and now the autopilot and autothrottle were turned off. I don't remember what speed we were actually flying because VNAV was still engaged. We decided to continue visually on the VASI; but perhaps fast? We received a momentary GPWS which I don't recall what it was alerting us for. We were stabilized; but we did have a flaps 25 indication. Normal touchdown and taxi to the gate where we wrote up the problem.
B737 flight crew reported the Number 1 left slat transit light was illuminated although the slat appeared to be extended. The trailing edge flaps could not be extended beyond 25 degrees and the approach was continued to landing.