ARTICLES

 

Rotorway Accident Statistics

As a helicopter flight instructor who also instructs in a number of home-built Rotorway helicopters I was curious to discover why there seems to be such a disproportionate number of Rotorway helicopter accidents as compared to the certified R22 and Schweizer 269/300 series light training helicopters. A visit to the NTSB accident synopsis web site was eye opening indeed when the actual causes of these accidents are grouped and studied.
The Rotorway helicopters are unique in that they are truly real helicopters that you can build, maintain, and fly yourself. They can also bite you in a big way if you do not obtain adequate training and perform the proper inspections and maintenance. It appears from the statistics that most accidents that have occurred were preventable by either better pilot training or thorough inspection/maintenance. Over the years I have witnessed some very good Rotorway pilots and also those who treat their helicopters like toys, ignoring the inherent danger of foolish actions on the part of the pilot.
If you look at the NTSB accident reports for the past 5 years you can gain a better understanding of the true reliability of the Rotorway helicopters. Here is a break down of what went wrong:
Mechanical failure-
Two secondary shaft failures at factory with no injuries
One engine mount failure with no injuries
One engine failure at the factory with no injuries
One ignition failure with no injuries
So, according to the reports, there were 5 accidents resulting from mechanical failure with no injuries to the pilots or passengers. Rotorway has redesigned the secondary shafts to a 35mm size and they strongly recommend that all existing 30mm shafts be replaced with the larger diameter ones. Note also that of the 5 reported mechanical failures in 5 years, three of them occurred at the factory in their own helicopters. That means that in the entire fleet of customer-flown Rotorway helicopters there were only two reported accidents resulting from mechanical failure that could not have been prevented by proper maintenance or preflight inspections and neither of those produced any injuries to the occupants of the helicopters.
Below I have grouped the NTSB accident reports with respect to their reported causes. This information is presented as an observation and I am not placing blame on any individuals for their actions or lack there of. It is my hope that we can all learn from the mistakes that others have made and in so doing become safer pilots with more confidence in our well-maintained and properly inspected helicopters. These are not all of the incidents that we have heard of, obviously some go unreported to the NTSB, but are the ones that have been reported and documented. They give us a window through which to view the most common reasons why Rotorways seem to crash.

Maintenance and pre-flight failures-
Lower secondary bearing loose, tail drive belt comes off (should have been caught on preflight inspection) no injuries
Improper installation of ignition lead (should have been caught when replaced and tested) no injuries
Collective push tube rod end lock nuts not tightened ( should have been caught on pre-flight) minor injuries
Valves not adjusted ( should have been during regular maintenance) serious injuries
Transport wheels not removed ( Preflight item) no injuries
Oil line leaking- fire- ( maintenance and preflight) no injuries
Loose oil line- fire ( maintenance and preflight) no injuries
Tail rotor belt frayed and slipping- post crash inspection revealed that all inspection panels were painted over and never removed for inspection ( maintenance and preflight) Fatal injuries
Main belts slipping due to coolant leak ( maintenance and preflight) no injuries
Improper ballast position- flew into trees- ( maintenance and preflight) no injuries
Pilot Error- Rotor RPM
Low Rotor rpm- (improper pilot technique-training)no injuries
Low Rotor rpm- (improper pilot technique-training)no injuries
Low Rotor rpm- (improper pilot technique-training)serious injuries
Low Rotor rpm- (improper pilot technique-training)no injuries
Low Rotor rpm- mast bumping (improper pilot technique-training)fatal injuries
Low Rotor rpm- (improper pilot technique-training)no injuries
Low Rotor rpm- (improper pilot technique-training)minor injuries
Low Rotor rpm- (improper pilot technique-training)minor injuries
Low Rotor rpm- (improper pilot technique-training)no injuries
Low Rotor rpm- (improper pilot technique-Un-rated pilot-training)no injuries
Dynamic rollover-(student pilot releasing controls) no injuries
Dynamic rollover-(student pilot forgot to un-tether helicopter on lift-off) no injuries
Fuel exhaustion-(improper monitoring of flight time-training) serious injuries

That is 10 reported accidents that were due to pilot error in allowing the main rotor rpm to decay causing a crash- this should be a wake-up call to get the proper training and to develop proper instrument scanning techniques
.
Pilot Error - Hovering downwind
Wind gust from rear (pilot technique and training) minor injuries
Wind gust from rear (pilot technique and training) minor injuries
Wind gust from rear (pilot technique and training) no injuries
Wind gust from rear (pilot technique and training) minor injuries
Wind gust from rear (pilot technique and training) minor injuries
Here again proper training would have prevented most if not all of these accidents

Pilot Error- Other
Carb ice- carb heat was on- (not monitoring carb heat gauge-training)no injuries
Carb ice- carb heat was on- (not monitoring carb heat gauge-training)no injuries
Dynamic rollover- skid contact with ground ( improper hover ht.- training) minor injuries
Dynamic rollover- skid contact with ground ( improper hover ht.- training) no injuries
Tail strike- (improper flair ht.-training) minor injuries
Tail strike- (improper flair ht.-training) no injuries
One possibly attempted suicide ( no mechanical failures) minor injuries

As you can see, there were only two reported accidents from mechanical failure in five years that did not occur at the factory and all the rest could have been prevented by the pilot/repairman. There have been many more mechanical failures that have occurred in the fleet of Rotorway helicopters but the vast majority of those failures have been discovered during regular inspections and maintenance. Other mechanical failures have caused emergency descents but with proper pilot technique the helicopter and the passengers lived to fly another day. Most mechanical failures that have occurred in the Rotorway fleet have been published, discussed, and addressed in detail in Rotorheads and various other forums. Preventive measures have been proposed to prevent similar failures from happening again. As we network together, between ourselves and RWI, we will continually improve the reliability of our helicopters.

Get the proper training and do your pre and post flight inspections, your pre-boarding walk around inspection, and all of the scheduled maintenance. This done you will have a very reliable and enjoyable experience with your Rotorway helicopter. Fly safe.


Orv Neisingh
R/H CFI