Control unit (46, 46') for an aircraft (1, 1') capable of hovering or for a flight simulation system of said aircraft (1, 1'), said control unit (46, 46') being programmed to receive at input at least a first signal associated with real or simulated flight parameters (ALT, OAT; ALT', OAT') of said aircraft (1, 1') and provide at output a second signal (VNE, VNE') associated with a forward velocity to never exceed of said aircraft (1, 1'); said control unit (46, 46') being programmed to: - process a third signal (GW, GW') associated with an actual or simulated weight of said aircraft (1, 1'); characterized in that said control unit (46, 46') is programmed to: - associate plurality of tables (T1, T2,.., Tn) to respective intervals (11, 12,.. Ij) of values of said third signal (GW, GW'); each said table (T1, T2,.., Tn) associating a plurality of values of said second signal (VNE, VNE') with a respective said first signal (ALT, OAT; ALT', OAT'; AEO, OEI, Power off; AEO', OEI', Power off'); - process said second signal (VNE, VNE'), based on said table (T1, T2,.., Tn) associated with the relative interval (T1, T2,.. Ij) of said third signal (GW, GW') and the respective first signals (ALT, OAT; ALT', OAT'); - receive at input a fourth signal (AEO, OEI, Power off; AEO', OEI', Power off') associated with at least one further actual or simulated flight parameter of said aircraft (1, 1'); - store a plurality of profiles of velocity to never exceed (High_VNE, Medium_VNE, Low_VNE) associated with respective said intervals (11, 12,.., Ij) of said effective weights (GW, GW'); - associate each said velocity profile (High_VNE, Medium_VNE, Low_VNE) with a respective set (S1, S2,.. Sj) of said tables (T1, T2,.. Tn); each said table (T1, T2,.. Tn) of a said set (S1, S2,.., Sj) being associated with a respective value of said fourth signal (AEO, OEI, Power off; AEO', OEI', Power off'); - select within said set (S1, S2,.. Sj) of said tables (T1, T2,.. Tn) the table associated with the respective said fourth signal (AEO, OEI, Power off; AEO', OEI', Power off'); and - using said selected table (T1, T2,.. Tn) to evaluate the value of said second signal (VNE, VNE'). said control unit (46, 46') being programmed to: - process a third signal (GW, GW') associated with an actual or simulated weight of said aircraft (1, 1'); - process a third signal (GW, GW') associated with an actual or simulated weight of said aircraft (1, 1'); characterized in that said control unit (46, 46') is programmed to: - associate plurality of tables (T1, T2,.., Tn) to respective intervals (11, 12,.. Ij) of values of said third signal (GW, GW'); each said table (T1, T2,.., Tn) associating a plurality of values of said second signal (VNE, VNE') with a respective said first signal (ALT, OAT; ALT', OAT'; AEO, OEI, Power off; AEO', OEI', Power off'); - process said second signal (VNE, VNE'), based on said table (T1, T2,.., Tn) associated with the relative interval (T1, T2,.. Ij) of said third signal (GW, GW') and the respective first signals (ALT, OAT; ALT', OAT'); - receive at input a fourth signal (AEO, OEI, Power off; AEO', OEI', Power off') associated with at least one further actual or simulated flight parameter of said aircraft (1, 1'); - store a plurality of profiles of velocity to never exceed (High_VNE, Medium_VNE, Low_VNE) associated with respective said intervals (11, 12,.., Ij) of said effective weights (GW, GW'); - associate each said velocity profile (High_VNE, Medium_VNE, Low_VNE) with a respective set (S1, S2,.. Sj) of said tables (T1, T2,.. Tn); each said table (T1, T2,.. Tn) of a said set (S1, S2,.., Sj) being associated with a respective value of said fourth signal (AEO, OEI, Power off; AEO', OEI', Power off'); - select within said set (S1, S2,.. Sj) of said tables (T1, T2,.. Tn) the table associated with the respective said fourth signal (AEO, OEI, Power off; AEO', OEI', Power off'); and - using said selected table (T1, T2,.. Tn) to evaluate the value of said second signal (VNE, VNE'). - associate plurality of tables (T1, T2,.., Tn) to respective intervals (11, 12,.. Ij) of values of said third signal (GW, GW'); each said table (T1, T2,.., Tn) associating a plurality of values of said second signal (VNE, VNE') with a respective said first signal (ALT, OAT; ALT', OAT'; AEO, OEI, Power off; AEO', OEI', Power off'); - process said second signal (VNE, VNE'), based on said table (T1, T2,.., Tn) associated with the relative interval (T1, T2,.. Ij) of said third signal (GW, GW') and the respective first signals (ALT, OAT; ALT', OAT'); - receive at input a fourth signal (AEO, OEI, Power off; AEO', OEI', Power off') associated with at least one further actual or simulated flight parameter of said aircraft (1, 1'); - store a plurality of profiles of velocity to never exceed (High_VNE, Medium_VNE, Low_VNE) associated with respective said intervals (11, 12,.., Ij) of said effective weights (GW, GW'); - associate each said velocity profile (High_VNE, Medium_VNE, Low_VNE) with a respective set (S1, S2,.. Sj) of said tables (T1, T2,.. Tn); each said table (T1, T2,.. Tn) of a said set (S1, S2,.., Sj) being associated with a respective value of said fourth signal (AEO, OEI, Power off; AEO', OEI', Power off'); - select within said set (S1, S2,.. Sj) of said tables (T1, T2,.. Tn) the table associated with the respective said fourth signal (AEO, OEI, Power off; AEO', OEI', Power off'); and - using said selected table (T1, T2,.. Tn) to evaluate the value of said second signal (VNE, VNE').