Interference-Unpin

[garykevinware]

After writing about last week's problem by Alain White, under Magee Theme, and other problems showing Black Interference, Brian Harley wrote in his book, Mate In Two Moves: The Two Move Chess Problem Made Easy, "In every case of Black Interference so far shown, White has been allowed to mate by reason of Black's cutting off self-control of a mating square, or a square of interposal on the mating line. There is, however, the possibility of the Black Interference unpinning a White unit, which proceeds to give mate."



J.E. Funk Good Companion Folder December 1926 #2

2 points for showing me a complete variation. Send your solution to me at garykevinware@yahoo.com , by next Wednesday. There is also a bonus problem, under Knight Wheel, worth a possible 5 points, and so 7 points are possible this week.

[garykevinware]

Here is the answer to last week's problem:
Funk #2-
1 e7 Rac3 2 Qxa4#
1...Rec3 2 Qxb6#
1...Ne5 2 Qd5#
1...Nf6 2 Qc4#
1...f6 2 Qd7#
"Black can unpin White in two ways; by withdrawal of the pinning piece (Withdrawal Unpin) or by self-interference on the pin line (Interference Unpin). Most important is the second method, and modern composers have done much intensified work in this direction, especially with regard to the White Queen. The record of five unpins of this piece, introducing distinct mates, has stood for several years, and one begins to doubt if it can be surpassed, although the fact that the task can be done with a flight-square, as in the above problem, was once considered a hopeful sign."
Here is a bonus problem, also showing 'Interference-Unpin'.



C. Promislo Good Companion Folder October 1917 #2

2 points for sending me a complete variation. There are also two bonus problems under Knight Wheel. Send your solutions to me, at garykevinware@yahoo.com , by next Wednesday. I will be posting the regular problem(s), later this evening.

[garykevinware]

Here is the answer to last week's bonus problem:
Promislo #2-
1 Re6 Nd5 2 Qd6#
1...Bd5 2 Qf8#
1...Bf5 2 Qf2#
"The threat, Qe5, is a correct mate, although the White Q remains pinned. There are no exceptions whatever to the rule that a pinned piece (the Black Q) must not move, exposing its K to check. The logic is perfect, for if after 2 Qe5+, Black could play Qxe5+, his K would be the first to be captured."
David Dana-Bashian said that that problem reminded him of the following problem by Kenneth S. Howard:



Kenneth S. Howard Chess Review December 1935 #2

2 points for sending me a complete variation, at garykevinware@yahoo.com , by next Wednesday. I will be posting the regular problem(s), later this evening.

[garykevinware]

Here is the answer to last week's bonus problem:
Howard #2-
1 Rd6 Qxa6 2 Qd7#
1...Rxa8 2 Qxb7#
1...Rc7 2 Nb6#
1...Be7 2 Qxc3#
1...Nf7 2 Qg4#