Date: 201702
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: B737 Undifferentiated or Other Model
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Climb
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Aircraft component: Emergency Extension System
Component problem: Improperly Operated
Reporter organization: Air Carrier
Reporter function: Pilot Flying; First Officer
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Workload; Distraction; Troubleshooting; Confusion
Second reporter function: Pilot Not Flying; Captain
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Equipment Problem Dissipated; Flight Crew Became Reoriented
Contributing factors: Aircraft; Human Factors; Procedure
Primary problem: Human Factors

Narrative: It started out as a normal layover. Captain and I discussed how we had such a good night's sleep and were ready for the long day home ahead of us. In the car ride to the airport we discussed the flight plan; weather and aircraft. We got to the gate ahead of schedule. We settled in and we started our normal routines. I did the walk around while the Captain briefed the flight attendants and started setting up the cockpit. We loaded up and pushed back early. There was a little congestion but we made it to the runway prior to our flight planned departure time. Everything was normal and checklists were complete. We started the takeoff roll uneventfully. I was the flying pilot. We accelerated through V1; Rotate; positive rate; gear up. Shortly after we were told to contact departure. At 800 feet I began to accelerate and asked for flaps 1 and then up. We were both wearing noise cancelling headsets so things are usually pretty quiet. I mentioned to him that the airplane was not climbing very well and he said that we were heavy. I know that Departure likes altitude over airspeed so I was trying to climb as fast as possible. That is when I noticed the Red and Green gear lights. I believe that I mentioned that to the Captain but really could not believe it. The gear handle was up and we had all the lights. It took me a minute to think about in and then I had a sinking feeling. I thought that I for sure did not see a gear pin installed in one of the gear assembly; probably the nose gear; because it is difficult to get up in the nose well to get a good look at it. Pulled out the checklist and proceeded through it. ATC wanted a fast climb and we initially told him we had a gear issue and would need vectors. We made the crossing restriction over the VOR and then were given a heading after that. The Captain finished the checklist and then asked if I would take the radios and the aircraft and he would contact Dispatch and Maintenance. I put the Autopilot on and took over the radios. While he was on the #2 radio the flight attendants called up front because of the noise and fact that we did not turn off the sterile light and chime. I told them too much; but I said we were dealing with a landing gear issue and that we were probably going back to the departure airport. The Captain overheard some of the conversation and told me to tell them that we would get back to them when we had a plan. After that conversation with the flight attendants; ATC inquired about our intentions and that is when I said that we would probably need to return. ATC gave us another heading. I began to set up both radios and the FMC for the ILS. The Captain came back from talking to Maintenance Control touched the Alternate gear door so that it is completely closed and the switch was activated and then raised the gear and all was good and quiet again. Then he looked at me and asked if I was good to continue. I thought about and said yes if we have the gas for it. He then said; worst case scenario we make a fuel stop. I programed the route back in and the FMC said we would land with about 5900 lbs of gas. We were scheduled to land with 7;100 lbs so we burned an extra 1000 lbs dealing with the issue. This was acceptable but we would monitor as we proceeded. We continued to our filed destination uneventfully.


Second narrative: Upon takeoff the gear failed to retract when I selected the gear handle up. I first noticed it as part of the After Takeoff Checklist as we had three green and three red gear lights. The F/O was the pilot flying. I made sure he was aware of our situation and that he was in control of the aircraft while I began looking for the proper QRH checklist. I was still working the radios as we made the turn eastbound on the departure and climbing with the gear down. We told departure that we were working a gear issue and needed to level and take some vectors so we didn't get too far from the airport while we worked the problem. Departure asked if we could maintain 15;000 and gave us an approximately easterly heading off the VOR. We accepted the clearance because we knew it gave us terrain clearance and the FO kept the speed back around 230 knots per the checklist. At about this point I handed the radios off to the FO so I could concentrate on situation management. I proceeded deliberately through the checklist and after I had completed the checklist (more on this later) we still had gear down and three green and red lights. We checked to be sure we had the gear pins in the cockpit as a forgotten pin seemed a likely cause of our problem. All of our gear pins were in the bag in the cockpit where they were supposed to be.The FO and I were talking back and forth as things progressed keeping each other apprised but we were both coming to the conclusion that an airport return was probably likely. We had lots of gas so we had plenty of time and we had gear down; so we were in a good position. I told the FO to keep flying and talking to ATC while I contacted Dispatch and Maintenance to see if they had any suggestions or ideas we hadn't come up with. Somewhere about this point I took a moment to call the Flight Attendants and let them in on the situation. It was quite loud with the gear down and I had intentionally not given them the double chime climbing out of 10;000 ft because I wanted them to stay in their jumpseats until we had a better handle on what we were dealing with. But now it was time to bring them into the information loop. I gave them a quick explanation about the gear and that we were still developing a plan. I asked them to stay in their jumpseats and I would call them back in a few minutes.I found a frequency for ARINC and asked for a phone patch to dispatch. The operator informed me the current frequency was busy but gave me a secondary frequency. I called ARINC on the secondary and set up a phone patch with dispatch. I gave the dispatcher a brief summary and asked them to include Maintenance Control on the call. It took a few minutes but we achieved a three way call and I explained our gear situation and that the checklist had not solved our problem. The call was very patchy and we had trouble hearing each other and communicating. I did hear maintenance mention the manual gear extension door located on the cockpit floor to the left of the FO's seat. I couldn't tell what he said about it but it did ring a bell with me. I reached back and checked the door and found it ajar. I closed it firmly and asked Maintenance Control if they wanted me to try cycling the gear now. There was no answer as we had lost contact with dispatch and Maintenance Control. I knew at this point what had happened because I realized as I opened and closed the manual gear door that the micro-switch located in that door had prevented gear retraction with the panel ajar. I took it upon myself to cycle the gear handle and it retracted. We now had a fully functioning aircraft and I knew exactly why the gear had not retracted on takeoff. I think one thing that assisted me in missing the critical statement about the manual gear extension door is the logic of the Gear Disagree Checklist. It is straightforward until step four. Step four gives you two choices: 'All red and green landing gear indicator lights are extinguished' in which case the checklistis complete or; 'any red landing gear indicator light is illuminated' in which case you go to step 8. We still had 'any red landing gear indicator light illuminated' in that all three were still illuminated. This led me straight to step eight which gave me the helpful information that flying around with the gear down increases fuel consumption and decreases climb performance and not the checklist is complete. Step four is a binary choice; you have to choose one or the other and in so doing the logic would never allow you to get to step five. This checklist logic chain leading me from step four to step eight skipped step five which is where the sentence about the manual gear extension door is located. I think either a logic flaw or wording flaw in step four helped me skip past the information that we needed for our problem.I also think that we rarely get to experience non-normal checklists in real-time. Most of the non-normal checklist we accomplish we do as a function of training. Many of those non-normals such as Rejected TO; Engine Fire or Severe Damage; etc. we are relatively familiar with.


Synopsis: B737 flight crew reported the landing gear would not retract after takeoff. Following a discussion with Maintenance; it was discovered that the Manual Gear Extension Door was not completely closed.