Reliability Test Planner (RTP) – and other “Pry-gRAMs                       


By Gary Pryor      

Page updated 24 Mar 2015


New: (Jan 14): Rel-Solver v2.0 (1 Dec 2013)

New: (Sep 12): Rel-EZ update v 3.1.4 Apr 2012

New: (Dec 10): TIR Parser/Sorter Combo – programs combined into one

New (Nov 09): RTP version 2.9 – “high 9’s” reliability

New: Programs verified to run on Win7.  Note, because of legacy issues, all DLLs installed to program folders and not shared (instead of Windows/Sys32 folder).


Note: All CoN’s extended by 1 year - memo



Welcome!  From this page you may download the latest version of the RAM Software Tools authored by Gary Pryor

 collectively known as “RAM Pry-gRAMs”.  


What are they?  A collection of software applications, written and provided to aid in the development and evaluation of Reliability, Availability, and Maintainability (RAM) requirements.


Reliability Test Planner (RTP)

A utility which simplifies the development of statistical reliability test plans for the exponential and binomial distributions.  By specifying test parameters (length, failures, consumers or producers risks), the OC Curves and risks can be quickly calculated and displayed.  The test plans may then be modified and tailored to meet your needs.  The program includes a Monte Carlo simulation and also is capable of calculating expected (average) test time.  Multiple test plans can be displayed, compared, and modified in real-time. 


·         Use MIL-HDBK-781 standard test plans, or develop original plans for exponential or binomial distributions

·         Plot multiple OC Curves for plan comparison

·         Manual or automatic marking of risks or other points on OC Curves

·         Multiple options for printing test plans, OC Curves, plan info in color

·         Run Monte Carlo simulations of your test plans for varying reliabilities, and plot results

·         Simulate Weibull or Normal distributions against exponential test plans

·         Automatic generation of families of related test plans

·         Includes reliability “solver”: By inputting three of four test parameters (length, # of failures, reliability, or confidence) instantly solve for the fourth parameter; and directly implement that test plan with RTP

·         Calculation of expected test time


Rel Test Planner v2.9


Zip file: 7.3 MB

Army Certificate of Networthiness (CoN)

(expires May 2019)

PDF file: 19 KB





A mini-version of the RTP, in that it is limited to fixed-length test plans, doesn’t do OC Curve graphing or simulations, and doesn’t show producers risks.  This program is installed automatically when installing the RTP.


Standalone Rel-Solver v2.1 Installation Files  


Zip file: 2.6 MB

Rel-Solver v2.1 Executable File (can usually run without running installation files)

Exe file: 76 KB

Army Certificate of Networthiness

(expires May 2019)



A generic Monte Carlo simulation of system(s) reliability, availability, and maintainability.  Rel-EZ can model one system or a group of systems performing a set of missions.  A system can be made up of multiple subcomponents, each having individual reliability and repair characteristics.  Spare components may be modeled in either active or standby redundancy.  Systems are simulated performing their mission profile, which include periods of active and inactive time defined by the user.  Individual components within the system can be turned on/off for various portions of the mission  Rel-EZ uses randomly generated exponential or normal failure times; and lognormal, normal, constant, or arbitrary distributions for the repair and administrative (ALDT) downtimes.  It is also possible to model single shot items by specifying a failure probability.  Multiple options exist for handling the replenishment of single-shot items.  Component failure times may be specified in any mix of units desired (i.e. hours, miles, cycles, etc).  Outputs include component, subsystem, and system level Mean Time Between System Abort (MTBSA), Mean Time Between Essential Function Failure (MTBEFF), Mean Time Between Unscheduled Maintenance Action, Operational Availability, Mean Time to Repair (MTTR); mission reliability; percent of time with “n” systems available; average number of systems operating; and, if desired, the average number of systems operating at preset increments throughout the mission(s) duration.

Rel-EZ Installation Files

Zip file: 3.3 MB

Rel-EZ User Manual

Zip file: 0.4 MB

Army Certificate of Networthiness

(expired – in process of re-application)



TIR Parser Sorter Combination (see individual descriptions below)

Note: This program can be downloaded and run without installation on many PCs (the necessary libraries are common and are often already installed.  If not, a full installation may be conducted.

TIR Parser Sorter Combination (executable only)

Exe file: 160 KB

TIR Parser Sorter Combination Installation Files

ver: 1.1 dated 8 Jun 2010

Zip file: 2.2 MB

Army Certificate of Networthiness

(expires Feb 2018)