Shrieker AP rockets are armor-piercing.
The value of configfile >> "CfgMagazines" >> "PylonRack_7Rnd_Rocket_04_AP_F" >> "displayNameShort" (Shrieker AP CfgMagazines entry) is "Anti Personen" in the German localization.
Unfortunately, "Anti Personen" directly translates to "anti-personnel" instead of "armor-piercing". The correct term would ideally be "Panzerbrechend" or alternatively "Panzerabwehr".
The current (wrong) translation means that pilots of aircraft equipped with Shrieker AP rocket pods are told by their MFD and ingame HUD that these Shriekers are an anti-personnel weapon system - which is far from the truth and leads to inexplicably poor effect on targets.