B737-800
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 240; Flight Crew Total 8000; Flight Crew Type 2000
Communication Breakdown; Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Flight Crew Became Reoriented; Flight Crew Took Evasive Action; Flight Crew FLC complied w / Automation / Advisory
Staffing; Procedure; Human Factors; Company Policy; Chart Or Publication
I happened to do the walk around as the bags were being loaded at JFK on a Boeing 737-800. I noticed the bags had been loaded up to the ceiling blocking off the Smoke Detectors / Fire Suppression system.  I asked the baggage handlers to unload the top bags to leave a gap and showed them the red Cargo line. I asked if they understood about the red Cargo Max Load line and why I was asking for the gap between the bags and ceiling. They did not know as no one told them.They were very worried about losing their jobs if they did not do a good job loading ALL the bags for the airline. It was quite a job to persuade them to offload bags; promising no punishment for doing so. They felt pressure from their Company. They were extremely fearful for their Jobs.I explained that the bags were blocking the fire detection and extinguishing system and that a cargo fire could be catastrophic with loss of passengers; crew; aircraft and airline and that it was better to leave bags behind and explain why to the company and that they would not be punished. It was a MAJOR safety Issue. I don't think they understood the reasons or consequences and were totally focused on getting every bag onboard. I asked them to pass the information on to their colleagues. They said they would; but for me to send an email to the Handling Company to tell them too. I informed the airline who have said they will take action.Normally the walk around is done as soon as you arrive at the aircraft; therefore either they are offloading the previous flight's luggage and cargo or haven't begun loading bags so you don't see the end result of loading in both holds. I was horrified; realizing that because of the timing of the walk around I had up until this point never seen the final loaded holds and so not picked up that the gap was not being left for the Fire System and not realized that the loaders thought they were doing a good job loading all the bags and unknowingly covering the Detection and Suppressing system.We have been flying around not knowing this; assuming that with the check on the load sheet; the loaders have loaded correctly INCLUDING no further than the red MAX Cargo Line. In these days threats of losing jobs by not meeting targets and contracting; this safety issue has somehow got overlooked. They just didn't know and because of timing of the walk around in normal procedures and good airmanship In checking first thing; we haven't picked it up until now. I have been flying the 737 for a few years now and have missed this!I am thinking that this must be happening worldwide on all types of aircraft at all Handling Agents due to the nature of short term jobs these days and targets and due to the timing of the walk around pilots are unaware this is happening and a major safety risk. They don't see the final loaded cargo bays as they are briefing by then and checking the loadsheet.Please could you share this with all aviation companies; pilots; engineers and Handling Agents worldwide as it may have been missed and is a serious safety risk.Maybe the loadsheet could be amended to include a sentence to mark off to say that the safety gap has been left clear across the whole of the cargo bay with no exceptions to ensure the operation of the Fire Detection and Extinguishing System. Then there is no doubt just in case the loaders interpret and load around the detectors up to the ceiling.Also increased training and awareness of the safety consequences to the baggage handlers who often are only temporary or on short contracts these days; just focusing on targets and to reduce the pressure from their companies with no punishment for bags left behind for safety reasons.I flew again out of JFK this morning and the same thing happened. So the message has not got to the Handling Agent yet or loaders. There must be a way to alert them quickly.
A B737-800 First Officer on a walk around found the Contract baggage handlers had loaded bags above the red bag restricted line which blocked the Smoke Detectors / Fire Suppression system. Bags were off loaded; but on a return trip; the same over height baggage load developed. Better education to mitigate this dangerous situation.