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Services & Rates

Effective October 1, 2021


UWAL hosts subsonic wind tunnel testing at the Kirsten Wind Tunnel for customers outside the university. UWAL is self-sustaining as the revenue it receives from its commercial customers covers all costs of operation, builds a reserve for medium term capital expenditures, and includes the 15.6% UW Institutional Overhead (for use of university utilities, groundskeeping, and other shared costs). This rate guide describes the most common services UWAL provides for its customers at the Kirsten Wind Tunnel. UWAL also has access to other facilities and is capable of providing additional services. Please contact us if you have special testing requirements.

Rates for the Kirsten Wind Tunnel (8' by 12'):

Service or Item
Regular Occupancy (minimum: 9 hours/day)
Overtime Occupancy
Idle-Time Day
Electronic Pressure Scanning
Internal Force/Torque Balance
High Pressure Air Supply
DC Power Supply (40kW)
Engineering Pre-Test Services
Formal Test Report
Pass-through costs
KWT cost plus sales tax (10.1%)
KWT cost


Sales Tax (or Use Tax) and UW Admin Institutional Overhead:

Washington State sales tax (or use tax, which has the same rate) does not apply to pure services or the incidental discs and documents normally output in the course of pure services. Therefore sales tax does not apply to most UWAL charges. The exceptions are tangible items such as excess material costs or trip dots. Thus, whenever UWAL passes through the cost of such tangibles for the convenience of on-site personnel, the pass-through cost includes whatever sales tax UWAL paid originally.


Description of services and UWAL policies

Daily minimum charge

UWAL charges by the work shift.

An hourly cost basis is listed above because most inquiries and gov't subcontracts ask for costs to be evaluated in hourly increments. The minimum charge per shift is the shift length hours specified in the Work Agreement times the Regular Occupancy cost-basis, plus any Overtime Occupancy.

Thus, a traditional 9-hour, 7:30 AM to 4:30 PM, daily shift costs $7,020.

KWT occupancy

KWT occupancy begins with test section preparation for model installation and ends with model removal and test section restoration to the standard aircraft-testing configuration. The standard business hours are 7:30 am to 4:30 pm, Monday through Friday, excluding University of Washington holidays.

The shift length specified in the work agreement can run to 5:30 PM for a 10-hour standard day, for which the charge would be $7,800. This is common for out-of-state customers.

Waiting to decide on a day-by-day basis whether or not to run late is perfectly okay, but it incurs the higher Overtime rate and is difficult to promise since we may have to scramble to get available personnel.

Work Agreements have occasionally been made that specify 12-hour shifts, 6:30 AM start times, 8:30 AM start times, etc., for various customer reasons, but they depended on staffing levels, seasonal bus schedules, and other circumstances. Inquire if non-traditional shifts are needed.

KWT occupancy includes the following:

  • KWT rental including use of UWAL PC's for viewing data and doing test-related tasks.
  • Personnel to operate the tunnel, reduce the data, and assist with model changes.
  • Support for force and moment data acquisition, flow visualization, digital photographs and video.
  • Reasonable amounts of office supplies and shop supplies.
  • Use of UWAL Plotting and Wind Tunnel Data Organizer software packages.
  • Preliminary test data, digital images, and run logs on compact disk (CD-ROM or DVD-ROM) in PC format, prepared at the conclusion of the test.
  • Final test data, digital images, and run logs on compact disk (CD-ROM or DVD-ROM) in PC format, following completion of final data processing, if needed.

Overtime policy

Overtime occurs whenever testing runs beyond the scheduled shift, or whenever testing is scheduled for a Saturday, Sunday, or University of Washington holiday. Overtime charges will be waived for time used to recover from Downtime. UWAL cannot guarantee that Overtime will be available.

Idle-time policy

Occasionally customers may find themselves unable to continue with their test campaign. Perhaps a required model part is temporarily unavailable or the test matrix was completed ahead of schedule. If all UWAL-provided services have ceased and the situation is such that UWAL personnel can work on other projects, then the Company representative may request a switch to Idle-Time beginning the next day (assuming a multi-day test).

If the need to switch to Idle-Time occurs during a standard shift, the rest of that shift will be charged per the Regular Occupancy Cost-Basis (typically, data reduction, and other processing of test outputs continues to occur).

Charging in blocks of half-days can be discussed with UWAL management.

(The old policy of having Idle-Time be an hourly thing created an amount of discussion grossly disproportionate to Idle-Time revenue. Also, one time, the rate for "Idle-Time" got copied into pricing forms supplied to a gov't customer agency, causing a contract rejection and subsequent cycle of paperwork revisions.)

Downtime policy

Downtime occurs whenever UWAL is responsible for a problem that takes more than 15 minutes to resolve and that prevents proceeding with the test. UWAL does not charge Tunnel Occupancy or Overtime rates during Downtime. Note that activities that are a part of UWAL's standard operating procedures, such as calibration routines or tunnel checkouts, are not considered Downtime.

UWAL makes reasonable efforts to ensure that its facilities are operational during scheduled tests. In the event that Downtime occurs, the facility will attempt to recover lost test time by offering additional test time, if available. For example, if the downtime causes a delay of one entire shift and no additional days are available after the scheduled end of test, then one option is to work extended (12-hour) shifts for the remainder of the test. UWAL cannot guarantee recovery of lost test time.

Electronic pressure scanning

UWAL has an Electronic Pressure Scanning (EPS) system, which is ideal for measuring large numbers of pressures. There is a per-test setup fee in addition to Occupancy time needed for doing the set up. There is no separate usage charge, but utilizing EPS requires zeroing, several minutes for a calibration run done on the order of each hour of usage, and other associated tasks. Attention to test management so that most EPS tasks are done in parallel to model changes, etc., keeps the impact on Occupancy low. If you would like to use EPS during your test please contact UWAL to discuss your pressure measurement objectives.

Powered model testing - Combustion engines

It is possible to do test runs with a test article’s combustion engine running.  Due to associated health hazards such as carbon monoxide exposure, a Standard Operating Procedure is must be followed that includes time for ventilation and requires that the carbon monoxide concentration in the test section and model deck drop to a safe level before personnel are allowed to work in those areas. There is no extra charge for this type of testing, but regular Occupancy Charges continue to accrue while ventilating during the hours of the Work Agreement's standard shift. Ventilation is done using two large exhaust fans on the top floor.

While airing out the wind tunnel circuit during recent powered tests with small, exhaust-producing engines, no CO was been detected in the Control Room or down in the UWAL shop, so work still got done. It is recommended to make a run plan such that engine-on runs happen late in the day, so that the wind tunnel airs out overnight (no charges outside contract's shift time). Contact UWAL to discuss your testing requirements.

Car or truck testing using the PACCAR turntable

The PACCAR Turntable (aka Vehicle Ground Plane) is in a UW warehouse near campus and has not been used since 2005. A wind tunnel test that utilizes the PACCAR Turntable will incur at least the Regular Occupancy charge. A policy on whether to charge setup and usage fees as was done in the past will be discussed when pertinent. Cost recovery for Q-calibrations and other turntable work will likely be desired.

2D testing

The 2D Wall System is on hand, but has not been used since 2004. A wind tunnel test that utilizes the 2D Wall System will incur at least the Regular Occupancy charge. A policy on whether to charge setup and usage fees as was done in the past will be discussed when pertinent. Cost recovery for Q-calibrations, F/M Balance calibrations, and other 2D Wall System work will likely be desired.


Formal Test Reports - Hardcopies - Discs for Test Results and Reports

Some customers choose to have UWAL produce a formal, Boeing ANP-Style report documenting test times, data reduction terms, data reduction equations, selected images, and pdf-versions of logs. Purchase of a test report includes printing and shipping of 1 or 2 hardcopies of the test report along with a disc (plus up to 3 copies) containing a digital version of the report in Adobe Acrobat PDF format, along with all of the test data and images. Additional hardcopies and discs may be purchased months or years after the end of a test depending on contractual or legal retention requirements.

Example of a cost estimate

This example cost estimate is for a customer interested in conducting a wind tunnel test of an aircraft. Electronic Pressure Scanning (EPS) data will be collected during some of the runs in addition to standard force and moment data. The proposed test matrix totals 150 wind-on runs (each run is a set of test points where only one parameter is varied, such as the angle of attack or sideslip.) The test matrix also calls for 30 model configuration changes. The customer wants a test report and for UWAL to supply trip dots.

Installation Time: 6 hours

Actual model installation times vary quite a bit depending on model complexity and the model manufacturer’s familiarity with our model support systems. Sometimes it’s as short as 2 hours, other times it’s 2 days. For this example, 6 hours is used as a rough estimate.

Wind-On Time For Data Runs: 18.5 hours

Assumes an average wind-on time of 7-8 minutes per run, including ramp up and ramp down. Run durations depend on number of test points and how much time EPS zeroes /cals add to data acquisition. Runs typically last 4-10 minutes at UWAL.

Wind-On Time For Flow-Viz Runs: 2 hours

The time needed for Flow-Viz varies greatly. Smoke flow takes 30-60 minutes to set up, China Clay requires time for clean up, Mini-Tuft runs take about 60 seconds per test point for the photography, etc., etc.

Model Change Time: 10 hours

Assumes model changes take 18 minutes on average. Note that some model changes may take several hours.

Tunnel Checkout and Daily Calibrations: 3.5 hours

There are a few daily tasks that wind tunnel personnel have to take care of, such as running a Bal Cal twice per day, checking the tunnel circuits, and inspecting fan blades. Much of this occurs while customers are working on their models, but even so, plan on about 45 minutes per day for these tasks. They are considered part of Occupancy.

Contingency Time: 2 hours

If a test plan is so tight that it cannot include a couple of contingency hours, then consider contracting for longer shifts or more days..

Model Removal: 4 hours

Total Time Required: 45 hours (or 5 days at 9 hours/day)

Tunnel Rental: $35,100 (45 Occupancy hours at $780/hour)
Electronic Pressure Scanning: $2,500
Trip dots: 20 ft at $18/ft (including sales tax) = $360
Test Report: $400

Total: $38,360