B767-300 and 300 ER
Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Aircraft Equipment Problem Critical; Inflight Event / Encounter Other / Unknown
Flight Crew Landed in Emergency Condition; Flight Crew Returned To Departure Airport; General Declared Emergency
Aircraft; Procedure
On flight departing ZZZZ for ZZZ; we experienced an uneventful initial departure. Approximately 25-50 NM north of XXX; climbing through approximately FL250; we received a EICAS caution of R WING SLIDE. It was accompanied by an overhead caution of EMER DOORS. As per the QRH; I had the flight attendants visually and aurally inspect the right wing. They reported that nothing abnormal could be seen on the wing but there was a banging noise on that side of the aircraft. Upon receiving this confirmation that a slide had most probably deployed; we declared an emergency with Center and returned uneventfully. Post flight inspection revealed that the Right Overwing Slide had deployed and departed the aircraft at some point.
When he and the First Officer saw the Caution light; they thought it was just a nuisance light; because they did not feel anything from the airplane or hear any particular noise. Only after they read the QRH procedure and asked the flight attendants to check the wing area did he realize the Right Overwing Slide had departed the aircraft. Reporter stated he saw two panels that were open when he checked the upper and lower wing area after landing. The upper panel on the side of the fuselage where the slide should have been and another panel on the lower fuselage belly almost underneath the overwing slide compartment were open. There was slide webbing material; lacings; couplings and two tubes (hoses) hanging from the slide container.  Recently; another pilot who had a maintenance background; told him to look for any raised section at the leading edge of the overwing slide compartment door panel.  The same pilot also told him that even a small rise of the door edge above the fuselage skin can cause the air to lift the door in flight. He believes that information could be very helpful for pilots to be aware of and have included in their preflight walkaround procedures.
During the climb passing FL250; around 30NM-to-50NM from [the] airport; we [received] the following EICAS Message: Right Wing Slide accompanied with Emergency Doors Light. We slowed down the climb speed and requested from ATC to level off. I glance at the pressurization and it was normal. The Captain contacted the cabin crew for any Visual or Aural indications. The flight attendants reported a clunking noise coming from the Right Overwing ramp slide area. As per the QRH; aural observations confirmed that the Overwing ramp slide had deployed and was still attached to the airplane. We declared an emergency and landed uneventfully.
Two pilots report an EICAS Message appeared for a Right Wing Slide accompanied with an Emergency Doors light illuminating during climb. Cabin flight attendants confirmed Right Overwing Slide on their B767-300 aircraft had deployed in flight. Emergency declared and air turnback accomplished. Post flight inspection confirmed inflight slide deployment and departure from aircraft.