Series 7750i
Ruska Laboratory
Air Data Test Set

Technical DataFeatures• High accuracy, RVSM compliant• Accuracy to ± 2 feet 0.02 knots• True differential sensor for airspeed (Qc)
• One year calibration interval• Automatic zeroing• Variety of Ps and Qc ranges available

For more than thirty years, we have provided
high precision Air Data Test Sets (ADTS) to theaerospace industry, airframe and component
manufacturers for testing avionics instrumentation used on a variety of aircraft from fixed-wing
to rotary to the space shuttle. The Model 7750i
Air Data Test Set represents the latest generation ADTS incorporating a unique quartz sensor
having unequalled precision and long term
stability with the latest pressure control technology. The Model 7750i ADTS provides highperformance measurement and control of all air
data parameters.
The Model 7750i is a laboratory ADTS
for calibrating a wide variety of avionics
instrumentation such as altimeters, airspeed
indicators, rate of climb meters, Mach meters,

air data computers and engine-based control
systems that rely on accurate control and measurement of pressure. The 7750i can be used tocalibrate devices that are required to meet theReduced Vertical Separation Minimal (RVSM)
requirements, controlling altitude to within
two feet (better than 0.003 in Hg) at sea level.
Additionally, the 7750i provides precision rate
control for both altitude and airspeed.
The Model 7750i is ideal for use in Automatic
Test Equipment (ATE) systems. The seven-inch
height (4U) allows easy integration into comprehensive test systems. Additionally, an IEEE-488
interface is provided for PC-based control. The7750i can be set to emulate previous generation
ADTS (Model 6610), eliminating the need toalter existing software.

Specifications
Automatic go to ground

Automatic zeroing

Upon selecting the go to ground command, the7750i safely controls the pressure to the current,
local barometric pressure. The user can thendisconnect the device under test (DUT) without
exposing sensitive instruments to a potential
pressure transient or shock.

As with any instrument, regular zeroing is suggested to achieve maximum performance. Thistask is now automated and can be performed at
the push of a button, or over the PC interfaces.
The 7750i incorporates the vacuum sensor
onboard; no separate or external vacuum gauges
or sensors are required. In addition, only one
vacuum pump is required to operate and zero
the 7750i ADTS. Zeroing is performed in 30 to
45 minutes using the specificed vacuum pump.

Leak test mode
A separate mode is provided for performing leakchecks prior to beginning an actual calibration.

Avionics and pressure units

Protecting the device under test

The Model 7750i displays the common avionics units including feet and meters for altitude,
calibrated airspeed in knots, km/hr, and Machwith corresponding rate displays for each unit
per minute. It can also display pressure units.

In order to protect the DUT, the operator canprogram high and low limit settings for:• Altitude• Airspeed• Rate of climb• Mach• Negative Qc• ARINC 565 envelope

High performance for fixed-wing orrotary aircraft

Although the standard configuration offered is aPs range of 32 in Hg and a Qc range ofAutomatic volume characterization
68 in Hg, we also offer custom ranges. For
The 7750i automatically tunes the controller into example, for exclusive testing of rotary aircraft,external volumes ranging from 80 to 1000 cubic a Qc range of 32 in Hg can be provided, increasing performance in the lower airspeed ranges.
centimeters (5 to 60 cubic inches). This allows
For other custom ranges please consult factory.
a large degree of flexibility for the configuration of the test system and the type of aircraft
and components to be tested. For component
manufacturers, a large number of devices can betested simultaneously on a single manifold.
ModeAbsolutePrecisiona

From 25 % to 100 % of FS: 0.005 % of reading below 25 % FS: 0.005 % of 25 % FS

Stability: Over 3 months
Over 1 year
Zeroing vacuum sensor

Differential

0.0019 % RDG/3 months

0.0019 % RDG/3 months

0.0075 % RDG/year

0.0075 % RDG/year± 10 mTorr (1.33 Pa) @ 100 mTorr

N/AControl stability

0.001 % FS

0.001 % FS

Control low limitb

0.3 in Hg abs. (10 mbar a)

0 in Hg in - Qc mode/0.3 inHg abs. in Pt mode

<0.004 % FS/24 hr.

<0.004 % FS/24 hr.

0 to 15,240 m (50,000 ft)/min

N/A

Zero drift
Rate of climb
Rate of climb tolerance

1 % of commanded to 15,240 m (50,000 ft)

N/A

Standard load volume

80 cm3 to 1,000 cm3 (5 in3 to 60 in3)

80 cm3 to 1,000 cm3 (5 in3 to 60 in3)

Mach

N/A

0 to 10.0004

Total uncertaintyc(aeronautical units)

32 in Hg a
Sea level ± 0.6 m (2 ft)
9,144 m (30,000 ft) ± 0.6 m (2 ft)
18,288 m (60,000) ± 2.1 m (7 ft)

40 in Hg a
Sea level ± 0.6 m (2 ft)
9,144 m (30,000 ft) ± 0.9 m (2 ft)
18,288 m (60,000) ± 2.4 m (8 ft)

32 in Hg D50 ± 0.1 knots
100 ± 0.05 knots
250 ± 0.02 knots

68 in Hg D
50 ± 0.2 knots
250 ± 0.04 knots
500 ± 0.02 knots
1,000 ± 0.02 knots

Total uncertaintyc(engineering units)

32 in Hg a
32 ± 0.0030
30 ± 0.0025 in Hg
15 ± 0.0013 in Hg
5 ± 0.0008 in Hg

40 in Hg a
40 ± 0.0037 inHg
30 ± 0.0026 in Hg
15 ± 0.0014 in Hg
5 ± 0.0009 in Hg

32 in Hg D
0.5 ± 0.0005 in Hg
16 ± 0.0013 in Hg
32 ± 0.0026 in Hg

68 in Hg D
0.5 ± 0.001 in Hg
16 ± 0.0016 in Hg
32 ± 0.0027 in Hg
68 ± 0.0055 in Hg

Precision is defined as the combined effect of linearity, repeatability and hysteresis throughout the operating temperature range. Some manufacturers use the word “Accuracy” in place ofPrecision,” however the meaning is identical.
Requires vacuum pump to control 0 psig, or the vent mode can be used to obtain 0 psig.
cTotal uncertainty is defined as the two sigma combined uncertainty of linearity, hysteresis, repeatability, thermal effects one year drift stability and the uncertainty in the Ruska primary
standard, which includes the uncertainty from NIST.
dLimits can be set to prevent excessive mach.
ab

2 Fluke Calibration

Series 7750i Ruska Laboratory Air Data Test Set

Specifications
GeneralElectrical power

90/260 V ac, 50/400 Hz, 150 W max.

Temperature

Operating: 18 °C to 36 °C (64 °F to 97 °F)
Storage: -20 °C to 70 °C (-4 °F to 158 °F)

Humidity

Operating: 20 % to 75 % RH, non-condensing
Storage: 5 % to 95 % RH, non-condensing

Weight20 kg (45 lb)

Dimensions (H x W x D)17.8 cm x 41.9 cm x 48.3 cm (7 in x 16.5 in x 19 in)

Pressure medium

High purity nitrogen or dry, clean air

Warm up time

3 hours

Digital interface

IEEE-488.2
RS-232Model 6610 emulation mode
SCPI syntax

Pneumatic connections

1/4 in FNPT on all ports. Adapters provided for AN6 and AN4

Supply pressure

60 psi ± 5 psi (4 bar ± 0.5 bar)

Supply vacuum

Minimum 50 liters per minute with auto-vent valve.
Ultimate vacuum less than 1 mtorr

Display
TFT active matrix color, 6.4 inch
Display resolution: 1 ft, 0.1 m, 0.1 kn/hr, 0.00001 Mach
Units
Altitudeft, meters

Airspeedknots, km/hr, Mach

Pressure

Engineering units: inHg at 0 °C and 60 °F, kPa, bar, psi, inH2O at 4 °C,
and 25 °C, kg/cm2, mmHg at 0°C, cmHg at 0°C, and cmH2O at 4 °C andfour user defined linear units of measure.
Aeronautical units: feet, meters, knots, km/h, Mach

RangesPs

Qc

7750i-80232

68

7750i-803

40

687750i-804

32

327750i-805

40

32

Control
Rate control indication
RoC: Rate of climb in all above units
RtAS: Rate of airspeed in Knots or km/hr
Total uncertinaty expression: 2 Sigma
Ps/32 inHg FS: RSS of 0.0091 % of Reading and 0.0008 inHg
Ps/40 inHg FS: RSS of 0.0091 % of Reading and 0.0009 inHg
Qc/32 inHg FS: RSS of 0.0091 % of Reading and 0.0007 inHg
Qc/68 inHg FS: RSS of 0.0091 % of Reading and 0.0012 inHg
Calibration
One year interval is recommended. Use of primary standard such as the Model 2468 Pitot Static
Gas Piston Gauge is recommended.
Options
Lines and fittings kit (supply and test lines) part number 7750-104
Vacuum pump_85 liter/minute capacity with auto-vent valve
Filter and muffler
National Instruments LabVIEW™ driver
ISO 17025 accredited calibration certificate

Fluke Calibration.	Precision, performance, confidence.™
Fluke Calibration
PO Box 9090, Everett, WA 98206 U.S.A.
Fluke Europe B.V.
PO Box 1186, 5602 BD
Eindhoven, The Netherlands
For more information call:In the U.S.A. (800) 443-5853 or
Fax (425) 446-5116
In Europe/M-East/Africa +31 (0) 40 2675 200 or
Fax +31 (0) 40 2675 222
In Canada (800)-36-FLUKE or
Fax (905) 890-6866
From other countries +1 (425) 446-5500 orFax +1 (425) 446-5116
Web access: http://www.fluke.com©2010 Fluke Calibration.
Specifications subject to change without notice.
Printed in U.S.A. 8/2010 3833786A D-EN-N

3 Fluke Calibration

Series 7750i Ruska Laboratory Air Data Test Set

Modification of this document is not permitted
without written permission from Fluke Calibration.