Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Overcame Equipment Problem; Flight Crew Returned To Clearance
Aircraft
For more than two years the FMS keypads have been known to display multiple numbers/letters when pushing one of the buttons. Such as attempting to enter 'ELP' with the result being 'ELLPPP'. This requires an attempt to delete the extra letters. However; the 'delete' key erases more than one letter and can delete the entire word. Under 'normal' operations; the flight crews have had to make this work by multiple inputs and deletes to get the desired input to the FMS. There is an aversion to 'write up' the FMS as it makes it unavailable for several days/weeks. During abnormal/diversion/missed approach conditions; the inability to enter data can lead to a pilot deviation or unsafe situation.  Such was the situation while approaching ELP airport with a thunderstorm over the field. With high wind and windshear reports and visible lightning; I asked for delay vectors as the weather cell was moving north; away from the field.  Approach was happy to comply with the following instruction: 'turn left heading 140; Hold on the ELP 140 deg radial; 15 dme; right turns; 5 mile legs'. I attempted to enter this info into the FMS several times but got worthless data on the scratch pad. I.E. EELPP1400///115 or ELPPP111440//155; etc. As we were rapidly approaching the holding fix; I had to revert to 'green needles' to display the radial and DME info. Unfortunately the First Officer was inexperienced and unable to add value to the situation other than to follow the commands I was telling him. We were late in beginning our initial turn outbound but were able to recover to the holding pattern once I gave him the DME numbers to begin the next turn.As we were in VMC conditions with the airport in sight; and only one other plane in holding below us; we were not in potential safety situation. However; this could have deteriorated quickly.  After a couple of turns in hold; we proceeded to a visual approach with no issues.Earlier this year I had a similar experience with multiple missed approaches at LAX where ATC was barking navigation fixes to proceed to. Again under stressful conditions I needed several attempts to get the correct info into the FMS.The situation with the FMS keypads is well known by the company who continue to dismiss it as nothing more than a 'nuisance issue'. In fact; I brought this topic up to the President on his first companywide conference call earlier this year. He claimed ignorance of the problem.
CRJ-900 Captain reported continuing problems with the FMS keypads displaying multiples of whatever character is input into the scratch pad.