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Designated Engineering Representative (DER) Data

(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:

  1. Are you an EASA Part 145 approved Repair Station?
  2. Are you located in the United States?
  3. Are you located in the European Union?
  4. Are you located outside the United States and the European Union?
  5. 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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