New Aztec Nacelles In final Approval Process

New Aztec Nacelles- In final approval process. This variation covers the hundreds of PA23-250 Aztec Models which are equipped with the factory-installed  or aftermarket Air-Research Turbo-Charging Systems.  Nacelle kits will be available for all Aztec models.  Call or email John Talmage at Montana Diamond Aire for more info. 

Montana Diamond Aire New Aztec Nacelles


Montana Diamond Aire New Aztec Nacelles

New Aztec Nacelles Update

Sneak-preview of the fiberglass/composite Aztec nacelles. The project is currently in the STC certification-plan approval stage. This aircraft has not been test-flown as of yet but we fully expect these nacelles to perform on the Aztec in the same manner as our previously approved nacelles perform on the 4-Cylinder Apache models.
This particular aircraft  is a turbo model but we also have them for the normally aspirated Aztecs. They are a 2-piece design to replace the stock 6 or 7 piece assemblies. The nacelles can be removed in 3 minutes, reinstalled in 5 minutes due to a 100% camloc attachment system and no need to remove the cowl flap section for normal servicing. They feature lower drag and improved engine cooling, along with an improved induction design. We fully expect that Aztec owners will be flying their aircraft with cowl flaps closed in cruise which alone increases cruise speeds by 5-8 MPH.

See Photos of Piper Aztec Tail Removal

We have posted photos of the Piper Aztec tail removal that was executed last week.

Follow this link to view them.

Our New Website

Our Updated Website

Our Updated Website


We have given our website a new look!  The updated site is now viewable in all browsers.

Aztec Start Up Video

Check out our engine startup test of our current project- complete Aztec overhaul.

Complete Piper Aztec Overhaul


Piper Aztec Complete Overhaul and Restoration Before

Piper Aztec Complete Overhaul and Restoration Before


The Piper Aztec pictured above is currently undergoing a complete restoration and overhaul.  Upgrades will include a new interior, custom paint job, new engines and nacelles, and instrument panel.  We will be posting the final “after” photos of this project once finished.

At Montana Diamond Aire we not only perform complete Piper Apache to Geronimo conversions but all types of modifications and upgrades for Piper Aztecs and Apaches.  Visit our website for a listing of our fully STC’d modifications or email .

Please note the performance chart below for the Piper Aztec if you are considering a twin-piston aircraft purchase.


Piper Aztec

Take-off Distance, 50-foot obsacle (Ft)


Landing Distance, 50-foot obsacle (Ft)


Gross Weight


Useful Load


Max Payload (Full Fuel)


Fuel Capacity


Range @ 65% Power


Cruise Speed @ 65% Power (Kts)


Rate of Climb (Sea Level)


Single Engine Rate of Climb (Sea Level)


Service Ceiling


Single Engine Service Cieling



Lycoming 250 Hp IO-540-C4B5

Total Fuel Burn/Hr


Link to Piper Geronimo Engine Test Pre-Flight Video From Today

We have posted a video from today on YouTube.  We’ll try to get more takeoff video footage tomorrow. 

The New Generation Piper Geronimo Flight Test Update

Piper Geronimo Ground Engine Test April 2009

Piper Geronimo Ground Engine Test April 2009


We will begin in-flight testing for the Lycoming 360IO 200 HP fuel-injected, roller-cam equipped engine Piper Geronimo later this week!  Keep checking back as we will be posting the results here as soon as we compile the data.

Montana Diamond Aire currently has Piper Apache airframes available for made-to-order conversions to Piper Geronimo.  Order yours today and be in the air by early 2010! 

The new roller-can fuel injected Lycoming 360IO engine upgrade is also available for our Apache to Geronimo conversions!  These are factory-new engines.

Press Accolades For Our Piper Geronimo Conversion!

Aircraft Marketplace Article
Aircraft Marketplace Article

We are pleased to announce that our Piper Apache to Geronimo conversion was featured as the “Bird of the Week” for April 22nd on the Aircraft Marketplace website.

To view the entire article, please go to .

Reliable and Economical Flight Multi-Engine Trainer

Piper Geronimo at Montana Diamond Aire

Piper Geronimo at Montana Diamond Aire

With the price tag for a new twin-engine trainer at around $750K, a Piper Geronimo conversion is an economical alternative and a rugged addition to any flight training program.

Powered by Lycoming 180 HP engines, this six-seat aircraft has the ability to take off and land on shorter fields easily clearing 50ft obstacles.

For a sampling on how the Piper Geronimo compares to the other popular multi-engine trainers, please visit our new weblog page

Montana diamond Aire currently has Piper Apache airframes availble for made-to-order conversions to Piper Geronimo.  Order yours today and be in the air by early 2010!

Engine upgrade to factory-new Lycoming 360Io 200HP fuel-injected roller cam equipped engines are available now for Piper Geronimo.  This upgrade is fully STC’d.

We will be updating our website, to include more detailed performance specs.

For more info on the Piper Geronimo, please email