Date: 201404
Local time of day: 0601-1200
Location: ZZZ.ARTCC, US
Flight conditions: IMC
Weather elements / visibility: Icing; Thunderstorm; Turbulence
Light: Night
Aircraft: MD-88
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Air Data Computer
Component problem: Failed
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Human-Machine Interface; Situational Awareness
Anomaly: Aircraft Equipment Problem Critical; Deviation - Altitude Excursion From Assigned Altitude; Deviation - Speed All Types; Inflight Event / Encounter Loss Of Aircraft Control; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued New Clearance; Flight Crew Regained Aircraft Control; General Declared Emergency
Contributing factors: Aircraft; Human Factors; Weather
Primary problem: Aircraft

Narrative: Flight was routine except for the line of thunderstorms we were deviating around. Level at FL320; light to moderate chop; a lot of lightning; continuous St. Elmos fire. My leg; we are working our way around some storms when the autopilot and autothrottles kick off. My concentration went 100% to flying the airplane while my First Officer (FO) began to troubleshoot. We tried turning them on a couple times but each time they kicked off. He then noticed a CDC 1 fail in his scratchpad. The QRH had him switch to both on 2. After a few moments we tried the autothrottles and the autopilot and both could be engaged. I believe we also had a route data dump with the FMC; but we recovered that pretty quickly. Shortly thereafter; the aircraft began vibrating. A quick scan of both sets of flight instruments showed us steady at around 280 knots; but a glance at the standby airspeed showed around 220 and decaying; but why? Power was normal; vertical speed was 0; but the standby said we were slowing. Very shortly after that; the stall warning went off; and down we went. We had previously checked the wiper for ice and found none so the wing anti-ice was off but the engine anti-ice was on. I remember asking to confirm all the heat was on and my FO checked all the indicators and turned the wings on. The plane continued to stall and buffet until about FL285 where control was regained and some semblance of order began to return to the flight deck. We had declared an emergency with ATC out of FL320; so we checked in with them indicating that we felt we were under control. We both agreed that the best course of action would be to continue to destination; and the remainder of the flight was uneventful. This event really surprised me. I can only think that; due to the weather; we encountered a rapid ice buildup. If that is the case; one thing we could do is; anytime engine anti-ice is on; wing anti-ice should be used as well.




Synopsis: MD88 Captain experiences airspeed indication failure; both left and right at FL320 while maneuvering around thunderstorms. While attempting to troubleshoot the stall warning activates and standby airspeed is noted at 220 knots. Control is regained at FL280 and the flight continues to destination. CADC 1 had indicated failure prior to the event and airspeed indication had been switched to both on CADC 2.