Air Carrier flight crew reported a fume event during climb described as musty 'locker room' odor. The Captain elected to request priority handling to execute an air return to departure airport. A safe overweight landing was accomplished and maintenance was requested.
Synopsis
Air Carrier flight crew reported a fume event during climb described as musty 'locker room' odor. The Captain elected to request priority handling to execute an air return to departure airport. A safe overweight landing was accomplished and maintenance was requested.
Narrative
Upon arrival in ZZZ on our second leg of duty period one; we were rescheduled to fly ZZZ-ZZZ2 instead of our published schedule of ZZZ-ZZZ1. FO (First Officer) and I proceeded to the ZZZ2 flight and when I arrived I was told by the Gate Agent that all passengers were either onboard or in the jet way waiting to board. As I made my way down to the aircraft I found approximately 15 passengers were still on the jet way and that the flight attendants had stopped the boarding process due to the ground power tripping off line and the aircraft being dark. The aircraft was also very warm and there was a musty smell in the cabin. Since the ground air conditioning had never been hooked up and the APU was not started; I assumed that this odor was a result of the aircraft sitting for a period of time in rainy and very humid conditions with no air circulation. I immediately started the APU and applied bleed air to the packs and the boarding process was completed. FO and I completed out pre-flight preparations and we pushed of the gate and taxied to Runway XXC and departed uneventfully. Passing 8;000 ft. on our climb out; we received a call from a flight attendant stating that a passenger was complaining of an irritating odor and a burning sensation in her eyes. I asked the FA (Flight Attendant) if they were experiencing the same thing and was told that they could still smell the musty; sweaty socks odor but no eye irritation. At that point I suggested that we wait a few minutes to see if the odor dissipates thinking that it may just be some moisture in the AC system that would burn off. After about five minutes I called all flight attendant stations for an update and I asked for a consensus on whether the odor was getting better or worse or staying the same. All the FA's agreed that the odor seemed to be subsiding and they were OK with proceeding to ZZZ1. It was then when FO stated that he could still smell the odor and that he was developing a headache. At that point I decided that we needed to return to ZZZ. After [advising ATC] we were cleared direct to ZZZ and we started our descent; notified Dispatch and ZZZ operation; completed all applicable check lists; QRH procedures and the over weight landing assessment. We touched down on Runway XXC in ZZZ at a weight of 188;800 lbs at 155 IAS and taxied to the gate uneventfully. At the gate all passengers were deplaned and I made the appropriate logbook entries in the Aircraft Maintenance Logbook. The flight attendants were met by someone who I believed to be an in flight Supervisor and were escorted off the jet way by them. FO and myself were the last two off the aircraft and when we reached the gate area; the flight attendants and the in flight Supervisor were nowhere to be seen.
Second reporter narrative
Last minute schedule change to ZZZ1. Arrived at mostly boarded aircraft (roughly 170 passenger). External power had failed. APU off; No external power; No external air. FAs (Flight Attendant's) had stopped boarding and were discussing deplaning when we arrived. First noticed a slight 'locker room' smell at that time. We believed it was a result of the high temp in the cabin with the passengers; in addition to the +TSRA and gusty winds in the area. Started APU and continued as normal. No increase in smell during APU or engine start. Climbing through 8;000 ft. FA called the flight deck stating a passenger was reporting a strong electrical burning and musty/dirty sock smell in addition to eye irritation. Captain and FA's believed it was OK to continue but they'd monitor the situation to see if it improved. About 10 minutes later it had become strong enough I was able to notice more and had developed a headache and suggested we return to ZZZ. Captain agreed and we [advised ATC]. CA (Captain) assumed PF (Pilot Flying) duties and radio. I accomplished applicable QRH procedures; check lists; and landing assessment. Returned to ZZZ for an overweight landing. Cancelled priority request on the ground. Deplaned at gate with no injuries or anyone requesting medical attention.Maintenance issue. Possible rain water in combination with other fluids pooled around heated or electrical components in the body of the fuselage. We didn't initially believe it was the aircraft producing the smell/fumes since it was purely on emergency battery power when we first arrived at the aircraft.Uncertain. Would need to know the cause of the smell/fumes.
More incidents for this aircraft family →
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.