http://www.onwar.com/chrono/1939/sep39/f25sep39.htm
Monday, September 25, 1939
Luftwaffe bombing Warsaw
In Poland... The Germans issue a second ultimatum to the Polish Warsaw garrison. Meanwhile, German forces step up their bombardment of Warsaw and add heavy air attacks to it. Some 400 Luftwaffe bombers and Stuka dive bombers make repeated sorties, starting significant fires. Hitler wishes to complete the conquest as soon as possible and since the garrison is fairly strong, it is necessary to force them to submit by terrorizing the civilian population. The bombing continues until the surrender.
In Germany... Bread and flour rationing is introduced. The distribution of food ration cards is completed.
In Berlin... Hitler issues his fourth war directive, ordering increased attacks on Allied shipping a swift conclusion to the war in Poland.
In the North Atlantic... After a near miss in an air attack, German propaganda claims that the British aircraft carrier Ark Royal has been sunk. This is the first of several such false claims during the coming months. The attack also marks the debut of the German Ju88 bomber.
Ju88: One of the most underappreciated aircraft of WWII. A German workhorse: Dive bomber, bomber, torpedo bomber, recon aircraft, night fighter.
“After a near miss in an air attack, German propaganda claims that the British aircraft carrier Ark Royal has been sunk. This is the first of several such false claims during the coming months.”
And one true one in November 1941. For two years Ark Royal was the workhorse of the RN, participating in most major operations.
From Robin Neillands' "The Bomber War":
"On 25 September the full might of the Luftwaffe was unleashed against Warsaw. This attack began at 0800 hrs and went on for hours, until a great pall of smoke hung over the city -- 'not an open city', intones the 'Luftwaffe War Diaries', 'but a beleaguered fortress; [the bombs falling ] not on the dwellings of civilians but on a deeply staggered defense system, manned by 100,000 soldiers'.
"The Luftwaffe claims that only 400 bombers were deployed over Warsaw, dropping 500 tons of bombs and 72 tons of incendiaries; other accounts double that number of bombers.
"Whatever their number, each aircraft made three or four sorties, and by nightfall the centre of Warsaw was little more than burning rubble.
"On the following day the garrison offered to surrender, and city fell to the Germans on 27 September. The bomber war had claimed its first victory."
So, we are looking here at somewhere between 1,000 and 2,000 bombing sorties, which makes it the rough equivalent of later allied "1,000 plane bombing raids."
More to the point -- these German bombing runs had the same psychological effect on the Poles as the American A-bombs did on Japan: they removed the victims' will to fight. Nothing the allies did over Germany ever accomplished that critical goal.