ACRP Problem Statement No. 13-10-11 Recommended Allocation: -- Airport Jet-Way Maintenance and Operation Impact on Aircraft ECS ACRP Staff Comments: The term, "ECS" stands for Environmental Control Systems, and was not defined in the problem statement. TRB Aviation Group Committees Comments: AIRCRAFT/AIRPORT COMPATIBILITY: Jetways, APUs, and preconditioned air systems are separate pieces of equipment, and may be owned by individuals as opposed to airports. Perhaps this area of study is best left to the vendors, although tracking of O&M could be an element of overall airport asset management. AVIATION SECURITY AND EMERGENCY MANAGEMENT: The research problem points to work already done in this area with regard to ASHRAE standards and FAA's lack of regulation in this area. The concern seems to be largely regulatory in nature and not specifically a research concern. It remains unclear if there is a need to pursue new standards given that general assessment of the current situation is that existing standards are not followed. Additional thought for consideration: This study addresses conditioned air (hot/cold) supplied to airline aircraft parked at a jetway [aka passenger loading bridge; aka jet bridge]. The air handler affixed to the loading bridge provides the conditioned air to the aircraft via 12”- to 18”-diameter flexible pipe/duct which is manually attached by ground crew to the parked aircraft. Ownership of loading bridges at US airports is 5/6th airport and 1/6th airline (proposer’s figures). The proposer is asking to survey the US to determine the condition and dedicated maintenance of all of these air handler units, associated parts, and the loading bridges themselves. Opinion: For the air handler unit and condition of the loading bridge to be as pervasively poor as the proposer asserts, the owning airports and airlines are at fault. Is a study whose resultant findings prove the proposer’s assertions correct necessary? No. It’s the job of the airports and airlines to attend to their equipment. Review Panel: Not recommended — There are already established maintenance procedures between owner/operator and manufacturer. There is no need for the proposed research. AOC Disposition: No funds allocated. No discussion. AACCRRPP Problem Number: 13-10-11 Problem Title: Airport Jet-Way Maintenance and Operation Impact on Aircraft ECS Research Problem Statement: A recent informal study provided data showing that there was significant variation in the quality of maintenance of jet bridge air supply unit s for aircraft. The jet way functions to support the aircraft by providing a source of power and air-conditioning and/or heating to the aircraft without using independent contractors for ground support equipment. This docking time includes aircraft flight crew changes, loading and discharging passengers, staying overnight, and/or staying for an extended period. While docked, there are times the entire aircraft and airport gate is unattended. Service connections (i.e. hoses, lines, ducts) are also part of utility service provided by the jet way. It appears that minimal maintenance of these service connections occur, and replacement only if a complete failure is noted. There are no routine checks and balances scheduled for these service connections. One of the important areas of impact is the severe damage that occurred to the jet way service air conditioning panels while stowing wires and hoses on top of equipment. This caused equipment access / protection panels to become severely damaged; in some cases, damaged to a point they no longer fit properly. This repeated panel damage reduces the filtering ability of the service units considerably. Another important observation was debris catchers for these units have been eliminated, broken or removed, most likely due to the rough handling of these connections. A secondary random observation occurred. Aircraft departing from any gate could have intentional contamination via powders, liquids, aerosols, or gaseous contaminants into the unprotected duct system from the jetway utility service. Such introduction would quickly and effectively impact cabin air and environmental hygiene. Crew and passenger response to such contamination would most likely occur hours later; well into a lengthy domestic or international flight. Units that have not received adequate maintenance have resulted in degraded performance of aircraft air conditioning. It is highly likely that all other US Air Carriers would be subject to the effects on aircraft environmental systems caused by ground systems that are not properly maintained. Airport jet-way supply air to the aircraft may be provided by building HVAC systems or by stand-alone HVAC systems. ASHRAE Standard 161, paragraph 6.3.3 requires air provided to aircraft during ground operations drawn from air in the building conform to ANSI/ASHRAE 62.1-2004. No requirement is placed on stand-alone systems that supply air to the aircraft. It is not clear which standard that jet-way systems must conform to. Lack of control of jet-way supply air systems leaves the systems vulnerable to contaminants, both from air quality and biological sources that would affect the health and comfort of the aircraft crew and passengers. Thirty four percent of the 178 jet bridge air handlers inspected were in need of immediate replacement of the flexible ducts that conduct air from the air handler to the aircraft. If this random sampling is representative of all US Airport then approximately 1400 flexible ducts are due for immediate replacement at US Airports. Manufacturers of flexible ducts, which range in cost from $2000 to $4000 each, recommend replacement of the ducts every 6 months to 3 years, depending on the severity of the operation. Not changing flexible ducts can result in safety of flight issues for aircraft if aircraft are not serviced to clean the debris from the system. Many aircraft operators may not be aware of the issue and the risk posed to their aircraft. Cost to remove the debris from an aircraft requires approximately 350 man hours at an estimated cost of $17,000. The cost to the US fleet of commercial aircraft from lack of jet bridge system maintenance, assuming a fleet size of 5000 aircraft would be $85 million additional cost to the airlines when performing heavy maintenance. Cost to maintain jet bridges is $45.9 million dollars per year to the owners of the jet bridge air conditioning systems. The problem is that the level of maintenance given to ground based aircraft air supply systems is not known. A broad study is needed to assess the range of maintenance practices for building and ground sources of air provided to aircraft. Recommendations for future steps may be determined once the severity of the problem is determined, and the potential risk exposure faced by the aircraft operators and the secondary risk to the airports. The study will need to consider the range of ownership of gates and jet bridges within the 89 hubs within the United States. The study should also consider any differences between airport owners of the 2869 gates and 3660 jet bridges that are airport owned, and the 1303 gates and 667 jet bridges that are airline owned. Airports have the opportunity to obtain grants through the FAA Voluntary Airport Low Emission Program (VALE) to install ground power and air sources that reduce airport emissions encourage use of airport services. It is not known if the annual maintenance cost of ground systems has been considered (estimated at $11K per jet way) or if there is a cost trade in some areas where utilizing APU power may be more cost effective and pose lower risk to the aircraft environmental control system. Alternatively, the study may indicate monitors for HVAC systems or more significant operational checks and procedures would be a more cost effective approach than the use of aircraft system auxiliary power units. Objective: The objective of this study is to assess current jet-way HVAC maintenance practices and procedures as they relate to delivery of conditioned air to aircraft ECS, and examine the impact of the current maintenance procedures and practices on long term aircraft operation and heavy maintenance requirements. The study will also identify the manner in which airports protect supply air systems to prevent contaminants and water from entering the supply duct when it is stored between aircraft uses. The study may indicate that a standard or regulation would be advised to prevent contaminated air from entering aircraft air supply ducting that could lead to long term degradation of the aircraft ECS. Research Proposed: The proposed research would necessitate a survey of the 89 hub airports and the US airlines within the US who own and maintain the 4172 jet bridges and other ground air supply systems. The study will examine the service frequency of the aircraft supply HVAC and associated ducting. The study will assess the range of maintenance practices. The study will require examination and ranking of ducts based on physical condition, and level of contamination such as moisture, mold, and, dirt. The study will examine potential standards and recommend whether a new standard is necessary, or if existing building standards are sufficient if properly enforced. Estimate of the Problem Funding and Research Period: Recommended Funding: The recommended funding level for this study is $500K. The approximate value of the project is based on the assumption that significant travel will be required of the 2 researcher(s) for approximately 18 months to examine jet-ways at the 89 hubs and, to perform other program activities. Research Period: A research period of 18 months will be necessary. 12 months would be utilized for planning and conducting the primary research, and 6 months would be utilized for reporting and interaction with the Transportation Research Board (TRB) committee. Urgency and Payoff Potential There is an urgent need to perform the study.