Narrative:

I was the flying pilot during the descent into ZZZ. While descending on the arrival; I deployed the spoilers (in speed brake mode) to 1/3 of the flight limit; without incident. A few moments later I further deployed the spoilers and the aircraft began a rapid roll to the right followed immediately by the autopilot disconnecting. After assuming manual control of the aircraft and returning to straight and level flight; an additional attempt to deploy spoilers with the autopilot disengaged (at time of deployment) was made and the same rolling motion occurred. The configuration synoptic showed the left spoilers stowed and the right spoilers deployed. We looked for an applicable checklist for this situation in both the QRH and aom (aircraft operations manual) without success. Due to the asymmetric deployment and resulting rolling motion we made an initial decision to land without using ground spoilers (auto or manual). We then attempted to get landing distance data for the no-ground spoiler condition. We checked the non-normal landing data options; the QRH and the aom and found landing distance data with manual (as opposed to auto) ground spoiler deployment; but no data for a no-spoiler landing. We contacted dispatch via satcom and spoke with both our dispatcher and a engineer to determine: 1. Is there a checklist we're not aware of that could address this problem? 2. Is there landing distance data available for a no-spoiler landing? 3. Is there anything else we should be considering prior to landing the aircraft? The answer we got was no; no and no. While still on the line with dispatch; I elected to try spoiler deployment one more time. Spoiler deployment was normal. I cycled the spoilers several times and each time the spoilers deployed normally (symmetrically) with no rolling motion at all. We decided to land with the spoilers disarmed and to deploy them manually after touchdown. The landing was uneventful and the spoilers deployed symmetrically when the handle was moved aft after touchdown. As far as ATC is concerned; we told them that we'd be unable to make two assigned crossing restrictions during our descent due to a problem we were troubleshooting. We notified them early and they amended our clearance each time to delete the restrictions. We ended up asking for long vectors while we were talking to dispatch. We did not declare an emergency; request priority handling or ask for men and equipment to be alerted because the system was working normally again. The primary purpose of this report is to highlight the lack of a checklist to address this problem and; more importantly; the lack of landing data for a no-ground spoiler condition. I would like to commend my crew for excellent CRM and everyone taking part in seeing this situation to a successful conclusion! I have filed an event report concerning this event.

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Original NASA ASRS Text

Title: MD-11 flight crew reported an asymmetrical spoiler deployment during descent. The crew reported there was no data available for a no-spoiler landing.

Narrative: I was the Flying Pilot during the descent into ZZZ. While descending on the arrival; I deployed the spoilers (in speed brake mode) to 1/3 of the flight limit; without incident. A few moments later I further deployed the spoilers and the aircraft began a rapid roll to the right followed immediately by the autopilot disconnecting. After assuming manual control of the aircraft and returning to straight and level flight; an additional attempt to deploy spoilers with the autopilot disengaged (at time of deployment) was made and the same rolling motion occurred. The configuration synoptic showed the left spoilers stowed and the right spoilers deployed. We looked for an applicable checklist for this situation in both the QRH and AOM (Aircraft Operations Manual) without success. Due to the asymmetric deployment and resulting rolling motion we made an initial decision to land without using ground spoilers (auto or manual). We then attempted to get landing distance data for the no-ground spoiler condition. We checked the non-normal landing data options; the QRH and the AOM and found landing distance data with manual (as opposed to auto) ground spoiler deployment; but no data for a no-spoiler landing. We contacted Dispatch via SATCOM and spoke with both our dispatcher and a engineer to determine: 1. Is there a checklist we're not aware of that could address this problem? 2. Is there landing distance data available for a no-spoiler landing? 3. Is there anything else we should be considering prior to landing the aircraft? The answer we got was no; no and no. While still on the line with Dispatch; I elected to try spoiler deployment one more time. Spoiler deployment was normal. I cycled the spoilers several times and each time the spoilers deployed normally (symmetrically) with no rolling motion at all. We decided to land with the spoilers disarmed and to deploy them manually after touchdown. The landing was uneventful and the spoilers deployed symmetrically when the handle was moved aft after touchdown. As far as ATC is concerned; we told them that we'd be unable to make two assigned crossing restrictions during our descent due to a problem we were troubleshooting. We notified them early and they amended our clearance each time to delete the restrictions. We ended up asking for long vectors while we were talking to dispatch. We did not declare an emergency; request priority handling or ask for men and equipment to be alerted because the system was working normally again. The primary purpose of this report is to highlight the lack of a checklist to address this problem and; more importantly; the lack of landing data for a no-ground spoiler condition. I would like to commend my crew for excellent CRM and everyone taking part in seeing this situation to a successful conclusion! I have filed an event report concerning this event.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.