I can't imagine the deployment of a Delta IV would be a concern to the Turks considering the submarine was tracked by the Norwegian Air Force and Navy the moment it left the Kola Bay. The Turks knew about its presence and would have been able to take the necessary precautions or preparations to meet it.
Photo from a Norwegian Air Force P-3C as the submarine, a Delta IV, travels to Syria in 2016. As per an agreement with Russia, when transiting Norwegian waters in the Barents Sea, between the Norwegian mainland and Svalbard archipelago, Russian submarines surface and open their hatches to allow their Norwegian observers to see what they're carrying.
A year after the Delta IV deployment Dimitrij Donskoj, a Typhoon class submarine was photographed near the Norwegian coast by the Norwegian Navy. We're pretty adept at following the Russians whether they're above or below the water.
Turkey would have been given access to the location of Russian submarines, above or below, by NATO command. It's not as if they'd be surprised by a Delta IV just showing up.
But not always on an equal level with NATO partners. Look at the Type 214 for instance. Offered to and accepted by the Turkish Navy, the Type 214 is a subperb submarine, but also a downgraded export variant of the Type 212A, which has features not found on the Type 214 like a low-magnetic hull and x-shaped stern planes.
Type 214.
Type 212.
You might say, "
What's the big deal? It's an export variant, only Germany uses the Type 212." But that's not the case. Italy does and Norway has signed a contract with Germany to jointly purchase a modernized, modified version of the Type 212A to replace our Ula class submarines, themselves a upgrade over the Type 209 with features like an x-shaped stern planes which aren't found on the Type 209s. Germany will purchase several of the submarines for its own navy.
Type 209.
Type 210.
Being in NATO does allow you better gear then most nations are afforded, but it doesn't automatically mean you're going to have the best gear. Even within NATO there are export tiers.