Turton doubling

A piece A moves along a line across a square (critical square) allowing another piece B of the same colour to move to the critical square. Then, B moves on the line in the opposite direction, being supported by A. B is stronger than A.

The difference from Loyd's clearance is that the critical piece preserves its supportive power of the other piece.

Three different forms are recognized:

  1. (Ordinary) Turton Doubling. Two like motion pieces are of different strength. The weaker one first makes an anti-meta-critical move, and subsequently the stronger one comes in front.
  2. Loyd-Turton Doubling. Two like motion pieces are of different strength. The stronger one first makes an anti-meta-critical move, and subsequently the weaker one comes in front.
  3. Brunner-Turton Doubling. Two like motion pieces are of the same strength.

See also: Loyd-Turton doubling; Brunner-Turton doubling; Loyd's clearance; Zepler doubling.

Alias: Turton.

Abdurahmanović, Fadil

Ellinghoven, Bernd

feenschach, 2009

1st Prize

Example: Turton doubling
h#4.5  (6+10)

1...Bc7 2.Ba7 b8=Q 3.Bxd4 Qb6 4.Be5 Qd6 5.Bxh2 Qxh2#

Turton wB-wQ, Loyd's clearance wB-bB, sacrificial clearance bB-wQ.

View in Helpmate Analyzer

FEN: 1bK5/1P6/8/1n6/3Pp3/5pBp/4pPpP/4r1nk

External links:

Bakcsi, György

Zoltan, Laszlo

The Problemist, 1995

4th HM

Example: Turton doubling
h#2.5 2.1... (10+8)

1...Rh5 2.Kf3 Qg5 3.Ke4 Qxd5#
1...Qe6 2.Kxg4 Rf6+ 3.Kh5 Rh6#

Turton & Loyd-Turton.

View in Helpmate Analyzer

FEN: 5nK1/1p1b1PPp/3P3Q/3p1R2/5PPr/4P1kn/3P4/8

External links:

Seider, Shlomo

Munich club-150 JT, 1987

Example: Turton doubling
h#3 2.1... (8+13)

1.Kf1 Qc7 2.Kg1 Bd6 3.Qf1 Bh2#
1.Qd3 Bxe7 2.Kd2 Qd6 3.Kxc3 Qxb4#

Turton and Loyd-Turton.

View in Helpmate Analyzer

FEN: 2K5/4p3/8/PPBp4/1pqPn1p1/2P1Pp2/1pb2bpQ/4k2n