What are the aerodrome services SRE and CEV?

When in doubt, check GEN 2.2 for a list of abbreviations.

• CEV
  Centre d’essai en vol
  Flight test centre
• SRE
  Elément radar de surveillance du système radar d’approche de précision
  Surveillance radar element of precision approach radar system

CEV and SRE are ATC services restricted to defense aviation. That's why you don't have information in the AIP. The procedures are only available in the DirCAM AIP (CAM is for Circulation Aérienne Militaire, military aircraft).

CEV

This service is provided to Direction Générale de l'Armement (DGA), the French Defense Procurement Agency, for its flight tests. CEV comes from the previous name of the DGA infrastructure: "Centre d'Essais en Vol".

• You may read about DGA / CEV in this Artigo da Wikipedia (Traduz Google).

• Only selected ATC centers provide a support to test flights on a specific frequency.

SRE

ATC service used for approach to military bases using a Search Radar Equipment (SRE) renamed Surveillance Radar Element as noted by ymb in a resposta dele

A SRE is a long range panoramic radar, part of a Ground Controlled Approach (GCA). The GCA is composed of two segments:

• One used before the actual approach, using the SRE to determine the position of the aircraft and then guide it to the Initial Approach Fix where the PAR radar takes over.

• The Precision Approach Radar (PAR) segment where the PAR is used to guide the aircraft to the runway threshold.

Difference between a SRE radar (left) and a PAR radar (right):

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A PAR procedure at Avord base looks like this:

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The PAR approach above for example requires a Tacan transponder in the aircraft, something civil aircraft don't have (they have only the DME portion).

Veja também: What is a SRE approach on PPRuNe. More aqui in French (Tradução do Google).