Full down auto from HV curve

RkyMtnHI · December 2, 2010

Topics like this is what makes this forum amazing.

Stan, i cannot thank you enough for putting yourself out there like you have.. this sort of stuff is what teaches the rest of us in ways we might never experience.

I hope everyone realizes how important it is to learn from folks like you; pilots that put their ego aside to help others while sharing what they have learned... it is indeed rare.

Thank you!

aloha,

dp

500E · December 2, 2010

Stan as said you did a real good job with the auto.

How are you progressing with instrumentation? and did you get any info regarding pull down\inspection after OT?

StanFoster · December 2, 2010

500E- I found out that my turbines max fuel stop was set to low, so it could be the turbine just didn't have enough fuel trying to satisfy my overclallenged collective arm. I have changed my main fuel solenoid to fail on, have a complete extra sealed battery that will run the turbines governor, and I now can lose all my batteries, and my charging system if it fails also. This backup battery is diode protected so as to keep its power going only to the governor and is constantly charged by the electrical system...........................DP. Thanks for your comments. I will say something about my ego. I have been blessed with teaching myself how to build curved stairways, then have made it a business where it is 100% of our family income. I have been self employed for over 20 years and I am a one man stairshop. I guess my point is that I am very proud to show off what I can do very well and equally show where my shortcomings are. I wouldn't feel honest if I only told half my story. I am proud to have anyone go to my website and look around. There you can also see my Helicycle pictures. My website is www.stansstairways.com

Stan as said you did a real good job with the auto.
How are you progressing with instrumentation? and did you get any info regarding pull down\inspection after OT?

StanFoster · December 2, 2010

500E- I have a single stage turbine that is next to impossible to overtemp.

Hot starts are unheard of. My TOT never reads more than 900 degrees. Stan

Stan as said you did a real good job with the auto.
How are you progressing with instrumentation? and did you get any info regarding pull down\inspection after OT?

iChris · December 3, 2010

I could have still saved this helicopter over less desirable terrain than the smooth grass I was given, and do this by not gaining airspeed and better use of my collective.

Stan

I wouldn't feel too bad about the airspeed gain. In your case, you needed to transition from a nose up climb attitude into an autorotation attitude. Remember, you're already on the back-side of the power curve at 40 kts. What that means is you need to lower the collective and level the nose to maintain your airspeed.

Since you were able to maintain your airspeed by bringing the nose over; you had additional kinetic energy that you could effectively use at the end to reduce your rate of descent and forward speed. That would position you for your final collective pitch pull and landing.

Look at the diagram below and note the relationships between descent rate, airspeed, and power required. Airspeed slower than 40 kts increases your descent rate and bleeds-off kinetic energy. However, since you maintained (or maybe even increased) your airspeed, your descent rate did not increase and you retained kinetic energy. Everything needs to be done effectively; you do not have time for error. You wouldn't have gained much by lowering the nose further since there was little time or altitude remaining. Below 100 feet it's difficult to recover additional airspeed. The key is to maintain your airspeed. Analyzing your video from the time of power loss (5:42) until ground contact (5:50) was 8 seconds. Eight seconds from 100 feet works out to a descent rate of 12.5 feet per second or 750 feet per minute.

Edited December 3, 2010 by iChris

StanFoster · December 3, 2010

Chris- Thanks so much for posting that HV diagram. I have never seen the section to the right posted along with one. One of my reasons for telling my whole story, both good and bad, was to receive varying tidbits of advice on improving my methods . I have received that from several here. Thanks again everyone, as I am a better helicopter pilot after receiving the advice and kudos here. Stan- back to flying in Illinois.

I wouldn't feel too bad about the airspeed gain. In your case, you needed to transition from a nose up climb attitude into an autorotation attitude. Remember, you're already on the back-side of the power curve at 40 kts. What that means is you need to lower the collective and level the nose to maintain your airspeed.

Since you were able to maintain your airspeed by bringing the nose over; you had additional kinetic energy that you could effectively use at the end to reduce your rate of descent and forward speed. That would position you for your final collective pitch pull and landing.

Look at the diagram below and note the relationships between descent rate, airspeed, and power required. Airspeed slower than 40 kts increases your descent rate and bleeds-off kinetic energy. However, since you maintained (or maybe even increased) your airspeed, your descent rate did not increase and you retained kinetic energy. Everything needs to be done effectively; you do not have time for error. You wouldn't have gained much by lowering the nose further since there was little time or altitude remaining. Below 100 feet it's difficult to recover additional airspeed. The key is to maintain your airspeed. Analyzing your video from the time of power loss (5:42) until ground contact (5:50) was 8 seconds. Eight seconds from 100 feet works out to a descent rate of 12.5 feet per second or 750 feet per minute.

mechanic · December 5, 2010

Hey Stan, Nice Helicycle and glad you had a safe touch down!

Here is a link to a Helicycle that crashed and rolled at my airport back in 08'. Not a whole lot of info in the report. They could not determine why the engine failed.

NTSB Report