Designated Engineering Representative (DER) Data
September 01, 2005
(Sept. 1, 2005) To better understand the impact of European Aviation Safety Agency (EASA) Executive Director Decision (ED) 2004/04/CF, ARSA conducted an informal survey to determine the number of DER (8110-3s) repairs currently in existence.
The survey asked five simple questions:
- Are you an EASA Part 145 approved Repair Station?
- Are you located in the United States?
- Are you located in the European Union?
- Are you located outside the United States and the European Union?
- How many DER-approved repairs (8110-3s) does your repair station hold?
ARSA received 195 responses identifying in excess of 26,000 DER approved repairs. This matrix provides a complete breakout of the data collected.
| Question | Yes | No | Total | |
| Q1. Are you an EASA Part 145 Approved Repair Station? | 183 | 12 | 195 | |
| Number of DER approved repairs associated with Q1. | 25,857 | 169 | 26,026 | |
| Q2. Are you located in the U.S.? | 177 | 18 | 195 | |
| Number of DER approved repairs associated with Q2. | 19,763 | 6,263 | 26,026 | |
| Q3. Are you located in the European Union (E.U.)? | 6 | 189 | 195 | |
| Number of DER approved repairs associated with Q3. | 2,318 | 23,708 | 26,026 | |
| Q4. Are you located outside of the U.S. and the E.U.? | 11 | 184 | 195 | |
| Number of DER approved repairs associated with Q4. | 3,945 | 22,081 | 26,026 | |
It should be noted that some responses indicate answers like 1,000’s, more than 1,500 per year, etc. In those cases ARSA took a conservative approach and only utilized the base number.
If the data is extrapolated the potential number of DER approved repairs for 1,250 EASA Part 145 approved repair stations is 176,619.
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