For validation of the proposed technical solutions on layout, modifications of design and equipment of the Descent Module (DM) a thorough 3-D volumetric modeling of the spacecraft and testing of modified and new systems and assemblies were carried out, among them:

• integrated drop tests in order to verify the strength of DM modified shell and equipment attachment points, functional check of new chairs and DM structure, determination of shock impacts onto the crew to verify landing safety;
• integrated air-born tests to check interaction of new, modified and derived systems and DM structure in flight conditions on the portion of parachuting and landing.

Descent Module drop mockup testing

During drop tests three drops with maximum speeds were carried out to verify DM structural characteristics and 8 drops to determine shock impacts onto the crew with a nominal range of landing speeds.

During air-born tests one carried out functional and performance check of modified systems during DM parachuting and touchdown, verification of speeds and shock impacts onto the crew during landing, an integrated check of interaction of modified DM systems and assemblies during their functioning on the portions of parachuting and landing. The air-borne tests were implemented using an experimental facility based on the Il-76 plane under the following programs:

• nominal landing with the main parachute system (MPS) - drop #1 took place on December 24, 1998;
  
• MPS deployment, simulation of main parachute failure, transfer to and landing with the reserve parachute system (RPS)- drop #2 is implemented on April 8, 1999;
  
• landing with MPS in the conditions corresponding to those that are available during launch vehicle failure on the initial part of spacecraft insertion into orbit, with MPS deployment at a height of five kilometers - drop #3 is carried out on September 1, 1999;
  
• MPS deployment, simulation of main parachute system brake parachute separation assembly failure, through which the deployment of the main parachute in air stream is excluded, transfer to and landing with RPS - drop #4 is performed on December 1, 1999.

Landing of the DM mockup dropped from the plane.

The performed development test of modified Soyuz TMA spacecraft has confirmed that, in accordance with modification purposes, the spacecraft provides:

• accommodation of a crew with an enlarged range of anthropometric parameters;
• crew staying and activities in the Descent Module on all flight portions;
• reduction of Descent Module speeds by 40-50% of nominal values and by 30-40% of maximal values at ground touchdown for all estimated landing cases;
• reduction of shock g-loads values at landing in accordance with decrease of landing speeds.