NTSB Report - May 2003

[Steve Chenoweth]

A report of a B-2B involved in an accident. Does anyone have any additional information?

http://www.ntsb.gov/ntsb/brief.asp?ev_i ... 0649&key=1

[n2141u]

Here's the story from the first one on the scene of the accident.

On Monday, May 5th, I flew a Brantly helicopter N2141U from Melbourne, Florida to the Lantana airport. I had made a contract to sell the aircraft. As a condition of that sale, I was to deliver the helicopter to Lantana and I agreed to give an orientation to his flight instructor. The buyer was a student helicopter pilot and wanted to buy the aircraft to continue his training and then to use it in conjunction with his work.

I arrived at LNA at noon. We weren’t supposed to meet until 3:00 P.M., so I had lunch and waited for the buyer. After he arrived, he told me that his instructor would meet us at 4:00 P.M. I was told that his instructor was a “high time” helicopter pilot with extensive experience in many various types of both piston and turbine helicopters. I was also told that the instructor weighed approximately 150 lbs. I had estimated that my helicopter had 7-8 gals. of fuel remaining when I landed, so we arranged to add 15 gals. of fuel for the orientation flight.

When the instructor, arrived, I took him through a very thorough pre-flight inspection and also took extra time to explain the design and features of the Brantly B2B. At that time, it was obvious to me that he weighed substantially more that 150 lbs. We strapped into the helicopter with me in the right seat and him in the left. After warm up and completion of all the pre-flight checks, I lifted the helicopter into an approximate 2-foot hover. It became immediately apparent to me that we were at or slightly above the maximum gross weight for the density altitude. The temperature had risen to the high 80’s and our combined weight was more than I had expected. I pointed this out to the instructor and told him that all we could do was some hovering maneuvers until we burned off enough fuel to get the weight down. I showed him that we were pulling the redline maximum of 25 inches of manifold pressure and that I was just able to keep the rotor RPM in the middle of the normal operating range. (400-472) I hovered slowly over to the hard surfaced ramp area and performed a couple of slow pedal turns while emphasizing how difficult it was to hold the rotor RPM. I than turned the controls over to the instructor for him to get a “feel” of the helicopter. He started to hover-taxi at a more rapid pace and the rotor RPM decayed below the redline. I told him that we had to land to “unload” the blades and restore the rotor RPM. He continued to taxi and I told him again to “put it on the ground”. He then slid onto the taxiway, but instead of stopping, accelerated into a “running takeoff”. This was a surprise to me, as he had not said a word to me during the entire flight up to this point except to acknowledge a communications check after the engine was started.

I did not notice if he had recovered the rotor RPM during the “running takeoff”. Almost immediately after he lifted us off the ground, I felt and made a comment about going through translational lift. He then made his first comment to me saying “Now, we’ll get the wind.” By that time we were 30-40 feet in the air and at approximately 40 MPH. I noticed that the rotor RPM was slowly decaying down below the redline and became immediately aware that we were not going to be able to sustain flight. Looking ahead, we would be going down either in the center of a small lake or onto a busy highway. At that time, I took the controls and commanded him to “Let loose of the controls. I’ve got the airplane!” He said “Ok”, but didn’t release the controls. I tried to turn back to the shoreline below me, but he had a death grip on the controls and I was fighting him as well as deteriorating performance of the helicopter. I got the helicopter turned to the near shoreline, but by that time, the rotor RPM had deteriorated below the redline and consequently the tail rotor was starting to lose effectiveness. We were headed back downwind so were into a “settling with power” situation which further compromised our situation. We did a slow 180-degree rotation and settled into the water in a marshy area approximately 30 feet from the shore.

As we went into the water, I tried to retard the throttle, but he still had a death grip on it and I was unable to turn it. Shortly after hitting the water, the helicopter rolled sharply over on its left side. I heard the rotor blades striking and breaking off as they hit the water. Then I heard the engine go to extremely high RPM before stopping. I was hanging from my seat belt and looked to my left where I saw the instructor struggling under water. I grabbed his head and pulled it out of the water. He then unfastened his seatbelt and exited the helicopter leaving me to fend for myself. I then unfastened my belt and exited out of the left side of the helicopter. When I found him outside of the wreckage, I asked him if he was ok and he replied in the affirmative. He then wanted to try to push the helicopter back upright for some reason. We gave it a try to no avail.

Bystanders were starting to arrive on scene and were shouting at us to “get out of there”. I waded ashore and only then became aware that I was bleeding badly from a head laceration. Someone brought me some paper towels to hold on my head and I waited there for the fire department to arrive.

After the fact, I was able to reconstruct the sequence of events, and I am angry with my self for allowing myself to be intimidated by an unknown “highly qualified instructor pilot”. I should have taken the controls away from him much earlier and not allowed him to put us into a non-recoverable situation.

Gary L. Karschnick

[Steve Chenoweth]

Thanks the first-hand account. What a horror story!

My own experience here in Texas shows that performance is limited more than indicated in the POH on a hot, humid day when approaching max gross weight. Since all engines have their unique performance characteristics, it something to really watch carefully.

[N2285U]

I talked to a friend that talked to Gary and he said Gary (the owner) let the instructor fly the helicopter and the instructor let the rotor RPM droop. Supposedly Gary had to fight him back for the controls. Who knows what really happened. I have found my Brantly does exceptionally well in hot weather. On a high humidity 90 degree day with 370 lbs of people and full fuel @ 1000' MSL I can perform max performance take-off's with power to spare. I have never had a problem with power or low rotor RPM. I think every machine is a little different and my mechanic says every Lycoming is definitely different in their power output.

[n2141u]

I just saw the final NTSB report and found that the "highly qualified" instructor did NOT have all the qualifications that he had bragged about. He had no Bell 47 time. In fact, all 950 hours of his experience were in a R-22, with the exception of 6 hours in a Bell 206. So he had no helicopter experience with having to manually maintain engine and rotor RPM. Had I known this, I would not let him go as far as I did. It also makes me mad that he claims that he never touched the controls during the entire flight. I guess he's scared of me sueing him or of losing his job. For your info, we had about 460 lbs. of people and about 22 or 23 gals. of fuel on board Outside temperature was about 90-degrees.

[seneca2e]

Interesting accident report by the owner himself. At one point he says they had about 40 mph speed. They must have really had the rpm bleed off before that because at that speed they should have been able to fly away. If you can hover and ease into forward flight you should be able to fly as you gain translational lift. I was shown this by a very high time instructor and it was a very valuable demonstration. But with 460 pounds and 90 degrees temp they must have overpitched the blades to where the rpm was allowed to deteriorate to the point of no return.

[Ron Spiker]

I'm daily teaching my students in similar conditions in the summer time. Not always quite that heavy, but definitely at the performance limits of the helicopter. You're right... If you can get these into ETL and still are good on your RPM, you should fly away. If you can hover for at least a few seconds, they will fly. BUT, you have to know how to handle it, get it through ETL then into the air. I show guys frequently how to take off with no additional collective input. On those hot or heavy days where you're already pulling 25"+ of MP just to hover, you can likely still take off without pulling more power, IF you know what you're doing. Wow, this is a hot topic for me, and I could go on for an hour. There have been so many accidents due to conditions (hot, heavy, etc.) and not taking off properly, letting the RPM bleed off, going full throttle, not getting through ETL, then crashing. Basically not knowing HOW to handle the machine at the upper limits of its power/performance. I see guys when trying to get through ETL, not climbing, RPM bleeding off, throttle rolled all the way on, perhaps starting to settle down a little, and what are they doing? PULLING more collective! This may seem natural... you want to climb so you pull collective. However, when you're not yet through ETL and the engine RPM is starting to hit or go below bottom red line, and you're at full throttle, you actually need to LOWER collective a bit. This will fairly quickly start bringing your RPM back up, help you get through ETL, roll off a bit of throttle because the RPM will now rapidly try to overspeed, get a bit more forward speed, slight aft cyclic and it will jump in the air, and you're off.

DISCLAIMER: I'm not recommending anyone try any maneuver or procedure that I discuss or mention without a qualified instructor. Before flying your Brantly at its upper limits of power available, fly with someone who can show you how its done, properly and safely.

Thanks, seneca2e, for getting me started!!! It's too late at night for me to get going on a topic like this!

[seneca2e]

Thanks for adding this info Ron. It's a subject that certainly deserves discussion as there have been quite a few of these it seems.

[bryancobb]

PER FORT RUCKER I.P.'S ....RECOVER RPM AT ALL COSTS! I DON'T CARE IF LOWERING COLLECTIVE CAUSES YOU TO HAVE TO HIT A WALL OR FLY INTO THE JUNGLE, DO IT.

[9121u]

THANKS RON for commenting on flying heavy. you would be the one to get good info from since you have tons of brantly hrs in all conditions this should be addressed every year for the up coming hot months. and this good info applies to any thing that flys....thanks again ....have fun be safe....

[tamflyer]

PER FORT RUCKER I.P.'S ....RECOVER RPM AT ALL COSTS! I DON'T CARE IF LOWERING COLLECTIVE CAUSES YOU TO HAVE TO HIT A WALL OR FLY INTO THE JUNGLE, DO IT.

Been there: (Ex USArmy IP),
Done that: ( used almost exact words... 'Thy rotor RPM is thy staff of life')

Thanks for the memories, Bryan.....
Great advice, Ron

******************************************************
The Ten Commandments of flying helos :

- He who hath inspecteth not his aircraft gives angels cause to concern him.
- Thou shalt not become airborne without first ascertaining the level of thy propellant.
- Let infinite discretion govern thy movement near the ground, for thy area of distruction is vast.
- Thy rotor RPM is thy staff of life. Without it, thou shall surely perish.
- Thou shalt not let thy confidence exceed thy ability, for broad is thy path of destruction.
- He that doeth his approach and alloweth the wind to turn behind him shall surely make restitution.
- Thou shalt maintain thy speed between ten and four hundred feet lest the earth rise up and smite thee.
- Thou shalt not make a trial of thy centre of gravity lest thou dash thy foot against a stone.
- He who allows his tail rotor to catch in the thorns, curseth his children and his children's children.
- Thou shalt not fly unless thou first have a type rating for thy craft!