Evacuation Slides: (copy of an FAA webpage)

The content below was copied on 9/17/2014, from an
FAA posting at this web address:
http://lessonslearned.faa.gov/ll_main.cfm?TabID=1&LLID=9&LLTypeID=10

In response to NTSB Safety Recommendations A-79-16, A-79-18, and A-79-19, the FAA undertook research and development testing which resulted in the issuance of new TSO-C69 slide and slide/raft fire resistance requirements, girt strength, and critical angle testing.

TSO-C69a, TSO-C69bTSO-C69c

1) TSO-C69a, “Emergency Evacuation Slides,” dated June 3, 1983, included the following changes:

  • Added new radiant heat testing requirements of inflatable emergency evacuation slide/raft material. The test required three specimens tested at 1.5 BTU/ft2 sec, and the resultant times to failure in which average time to failure must not be less than 90 seconds. Time to failure is the time between first application of heat to the specimen and first drop in pressure below the maximum pressure attained in the test cylinder during the test.
  • Updated the slide/raft material flammability requirements to comply with paragraph (b) of section 25.853, “Compartment interiors,” (14 CFR 25.853(b)).
  • Revised the slide/raft strength requirement: “The device, installed at its critical angle, may not collapse when loaded to its maximum capacity as determined by a test in which a sufficient number of adult (170 pounds or more) evacuees crowd closely in line at the top of each lane of the device and jump into the device in rapid succession at a rate not less than one evacuee per second per lane. It must demonstrate the means used to connect the device to the airplane (girt material) will not fail when the device is operated at low angles (from horizontal) and at maximum evacuee loading conditions (including asymmetrical loading) expected in service. Also, the angles and loads selected may not be greater than 30 degrees and less than 1,050 pounds per lane, respectively. If the device is equipped with outrigger pontoons, additional test loads must be applied to account for asymmetrical loads that would result from evacuees inadvertently entering the pontoon areas during an emergency evacuation.

20140917cpy.. Evac Slide pics copied from FAA's 'LessonsLearned' Post

Photo of slides deployed
Photo copyright Yusu Ren – used with permission
Photo copyright Ronen Eckstein – used with permission

Additional Slide/Raft requirements beyond the NTSB recommendations were also initiated by the FAA to increase passenger/crew survivability

  • Evacuation rate increased from 30 evacuees to 60 evacuees per minute per lane at representative sill heights for a duration of at least 70 seconds.
  • Inflation time decreased from 25 seconds to 10 seconds after the actuation of the inflation controls begins. An additional wing-to-ground slide now requires the device to automatically erect in 15 seconds after actuation of the inflation control.
  • Slide/raft devices must be equipped with side guards or other means to prevent evacuees from accidentally missing or falling from the device.
  • Self illuminated slides must be designed so the illumination means is activated automatically during deployment or inflation and the level of illumination meets the appropriate requirements in 14 CFR 25.812.
  • Slide/raft must have the capability, in 25-knot winds directed from the most critical angle, to deploy and with the assistance of only one person, to remain usable after full deployment to evacuate occupants safely to the ground.
  • At least five consecutive deployment and erection tests must be demonstrated without failure to ensure that the slide/raft device performs its intended function. Section 25.809, “Emergency exit arrangement,” (14 CFR 25.809) contains requirements pertaining to the deployment and erection characteristics as well as the installation of the device on the airplane, which may be taken into consideration along with the requirements of this TSO.

2) TSO-C69b Emergency Evacuation Slides, dated August 17, 1988, revised:

  • Inflation time to decrease from 10 seconds to 6 seconds after the actuation of the inflation controls begins. An additional wing-to-ground slide now requires the device to automatically erect from 15 seconds to 10 seconds after actuation of the inflation control.

3) TSO-C69c Emergency Evacuation Slides, dated August 18, 1999, revised:

  • The slide/raft material flammability requirements to comply with paragraph (a) of 14 CFR 25.853(a) and the criteria described in paragraph (a)(1)(ii) of Appendix F, part I, of 14 CFR part 25.
  • Evacuation rates to increase from 60 evacuees to 70 evacuees per minute per lane at representative sill heights for a duration of at least 70 seconds.
  • Radiant heat testing requirements of inflatable emergency evacuation slide/raft material. The pressure holding materials in the device must meet the 90-second minimum-time-to-failure requirement and the 180-second average-time-to-failure requirement of the radiant heat resistance test.

(Aircruiser Slide Deployment video) — [aiR NOTE: short video showing a test deployment, no passengers.]

(Boeing Model 777 evacuation demo video) — [aiR NOTE: 4/17/1996 video showing test deployment and use by numerous test passengers. Note the use of two slide lanes at a time, though the passengers tend to wait for each other, thus the flow rate is far below 70 evacuees per minute per lane. Note also the compression at the bottom of the slides, where evacuees are crashing into one another and obstructing the flow of the next sliding evacuee.]