A ducted-fan airplane that didn't make it to market
We wrote the book! Ducted Fan Design, volume I | A ducted-fan UAV

Mass Flow

Ducted Propulsors

Founded 1995


Develop ducted fans powered by conventional piston engines

Design ducted-fan-powered light aircraft

Develop pylon-mounted ducted fan "pods" for larger aircraft and for retrofit to existing types

Provide consulting services in support of projects requiring ducted propulsors

Inform engineers, designers and amateur builders of the advantages, limitations and design constraints of ducted fans 

Email Forum for Ducted -Propulsor Discussions

As free email listservers have sprung up, we have taken advantage of the opportunity to create an on-line forum for discussion of ducted propulsors, including air-breathing systems, waterjets and even augmentors when used for propulsion. You can use this link to subscribe by email (just send the blank message), or use this link to use the Web interface to subscribe and set your subscription options. This service is free of charge, and can easily be cancelled, so please do not hesitate if you think you might be interested. We look forward to talking to you!

Reprints of Technical Reports

A list of ducted fan technical reports in our files, which we will reprint on request, is available on Archivale. You can order reprints on-line, using your credit card.

Our book, Ducted Fan Design, Volume 1

Use this link to view sample chapters of the new (2001) edition of our book, Ducted Fan Design, volume I , and hopefully to order it. On-line ordering (PDF or paper) using your credit card is an option there, but you can also order a paper copy directly from CreateSpace here.


Redesign of the Jethawk II fan and duct. The Jethawk is an amateur-built single-seat airplane powered by a buried ducted fan driven by a two-rotor Mazda rotary. It resembles a military jet, but uses conventional light airplane materials and techniques in its construction. It is structurally and aerodynamically sound, but the performance of the ducted fan falls well below expectations because fundamental errors were made in its design. Mass Flow was first formed to redesign the propulsion system of this machine, which its designer no longer supports, in order to rescue the 350+ enthusiasts who purchased plans and were later disappointed by reports of poor performance. We intended to offer change sheets to the original plans and to sell specialized components such as extension shafts and support bearings. Unfortunately, the market did not materialize - very few projects were actually started, and builders are understandably reluctant to start a project that they know will require major deviations from the plans that they have.
Status: Analysis of as-built system complete. Duct and fan redesign routines complete. Test article (complete JH II fuselage truss) in-house. No further work in prospect.

Publish a practical design manual for ducted fan design The first volume of Ducted Fan Design has been well received by readers on four continents; Volumes 2, 3 and 4 are in various stages of preparation.. A table of contents and sample chapters for V. 1 are now viewable on-line.

Other Ducted Fan and Shrouded Propeller Links
[No endorsement by Mass Flow is implied!]


Mass Flow
P.O. Box 3841
City of Industry, Calif. 91744-9991 USA

Email: massflow@archivale.com