venom 66 Posted January 24, 2010 Share Posted January 24, 2010 I have a question for the prop guys: as a crew chief, i was taught that when you feathered a prop,everything was shut off. hyd fluid,oil,elect,fuel, etc. A man by the name of Eric L Haney was a delta force operator and in his book,'inside delta force' he states that on that failed hostage rescue mission in iran in the middle of the desert in 1980, that the 130 he was on,'the engines continued to run,but the props were feathered'.All of my teaching says thats impossible. Or was he mistaken? Did they feather the props and he heard the GTC running? Would the crews even have shut down the eng's in that circumstance? Anyone know any extra info that they are allowed to share? thanx guys. Quote Link to comment Share on other sites More sharing options...
C130CC Posted January 24, 2010 Share Posted January 24, 2010 I don't know the particular instance, but he most likely thought he knew what he was talking about but misstated it. I am not familiar with that book so did he say they feathered them in flight or on the ground? Quote Link to comment Share on other sites More sharing options...
Skip Davenport Posted January 24, 2010 Share Posted January 24, 2010 (edited) I don't know the particular instance, but he most likely thought he knew what he was talking about but misstated it. I am not familiar with that book so did he say they feathered them in flight or on the ground? The aircraft was on the ground. There were 5 other Herks + the Helos there that night all with engines running blowing sand, minum visability and the burning bus. I as a Talon pilot knowing this crew think they were initially momentary, stunned, surprised by the explosion and confused by what was happening to them. There was most likely a few seconds delay before deciding to shut down/feathering the engines. Also, it takes a few rotations before they actually feather. If I recall from the photos in the book "The Guts to Try" the props appear to be feathered. Just my 2 cents. Edited January 24, 2010 by Skip Davenport Quote Link to comment Share on other sites More sharing options...
John H Wilson Posted January 24, 2010 Share Posted January 24, 2010 It is impossible for those engines to keep running if feathered.. If you pull the fire handle all those valves you mentioned are shut off... When you pull the fire handle every thing is shut off electricly.. When you pull the condition lever the fuel is mechanically shut off, and the prop feathers and your other valves stays open... If the GTC was not running at the time of the feather the props would not have enough electric power to go all the way to feather .. Quote Link to comment Share on other sites More sharing options...
C130CC Posted January 24, 2010 Share Posted January 24, 2010 The aircraft was on the ground. There were 5 other Herks + the Helos there that night all with engines running blowing sand, minum visability and the burning bus. I as a Talon pilot knowing this crew think they were initially momentary, stunned, surprised by the explosion and confused by what was happening to them. There was most likely a few seconds delay before deciding to shut down/feathering the engines. Also, it takes a few rotations before they actually feather. If I recall from the photos in the book "The Guts to Try" the props appear to be feathered. Just my 2 cents. Ok I remember this now, I saw a documentary on the History channel about it. Quote Link to comment Share on other sites More sharing options...
C130CC Posted January 24, 2010 Share Posted January 24, 2010 If the GTC was not running at the time of the feather the props would not have enough electric power to go all the way to feather .. I don't believe this is true. I have seen on more than 1 occasion crew chiefs put on DC power to check fuel/lox etc and watched a prop go into feather. The DC system if charged should have plenty of power to throw the props into feather. Quote Link to comment Share on other sites More sharing options...
John H Wilson Posted January 25, 2010 Share Posted January 25, 2010 I'v been retired for 6 years,,, but if I remember right the only thing the battery will do is shut off all the valves to that engine, and not feather the prop... I will get the answer tomorrow unless some one else gives us the answer... Quote Link to comment Share on other sites More sharing options...
BobWoods Posted January 25, 2010 Share Posted January 25, 2010 If I remember right the prop airstart/feathering pump is AC powered. Quote Link to comment Share on other sites More sharing options...
C130CC Posted January 25, 2010 Share Posted January 25, 2010 (edited) battery bus tie EDIT: The fire handle must be pulled for this to work. Let me do some research, I have been off work for 3 weeks because of the birth of our baby My brain is fried. Looks like to me that the DC bus will power the pump if the condition lever is left to feather. Am I looking at that wrong? Edit: Another thing I found. FUNCTIONS OF THE FIRE HANDLE There are 9 things that happen when you pull an engine fire handle. Remember BEEFF SHOP 1. Bleed air regulator closed. (ESS DC) 2. Extinguisher agent discharge switch is armed. (Battery) 3. Extinguisher system control valves positioned. (Battery) 4. Fuel shutoff valve at fuel control closed. (ESS DC) 5. Fuel shutoff valve at firewall closed. (ESS DC) 6. Start circuitry for engine de-energized. (ESS DC) 7. Hydraulic shutoff valves at firewall are closed. (ESS DC) 8. Oil shutoff valve below oil tank closes. (ESS DC) 9. Prop is Feathered. (ESS AC and ESS DC) Edited January 25, 2010 by C130CC Quote Link to comment Share on other sites More sharing options...
AMPTestFE Posted January 25, 2010 Share Posted January 25, 2010 You're missing the feather pump motor relay in the lower part of your schematic. The ESS DC energizes the aux feather motor relay, allowing ESS AC to power the aux feather motor. There is no way in hell this old prop will feather statically without ESS AC, no way no how. Quote Link to comment Share on other sites More sharing options...
BobWoods Posted January 25, 2010 Share Posted January 25, 2010 It seems to me that at the school house we used to pull the three C/B's for the aux feather motor and shut one down in flight as a demo to students pilots and FE's that it would feather without AC power. Could be that at one time it was on the FCF check list Quote Link to comment Share on other sites More sharing options...
C130CC Posted January 25, 2010 Share Posted January 25, 2010 I could swear that with battery placed in DC and the bus tie switch tied and ac inst and fuel cont inverted and you yanked the fire control handle with no external power that the prop will feather... Quote Link to comment Share on other sites More sharing options...
Dan Wilson Posted January 25, 2010 Share Posted January 25, 2010 Nope, no Ess AC, no (true) feather. Anything DC is just for the valves and relays, and there is no way to tie the inverter power into the aux feather motor. If you shut down the engine inflight without the aux feather motor having power it may move toward feather if the blade angle is high enough but those throttles would have to really be up there. Also, even if your prop does move towards feather I am pretty sure there wouldn't be sufficient air pressure to engage the feather latches. Dan Quote Link to comment Share on other sites More sharing options...
C130CC Posted January 25, 2010 Share Posted January 25, 2010 I'll give up on it for now, but when I get back to work tuesday I will get out the full schematic, cause I don't know where I am getting this in my head. Quote Link to comment Share on other sites More sharing options...
larry myers Posted January 25, 2010 Share Posted January 25, 2010 Without AC power on the acft. there is no way the prop will feather. The prop feather motor runs on three phase AC. Quote Link to comment Share on other sites More sharing options...
John H Wilson Posted January 26, 2010 Share Posted January 26, 2010 We use to pull those breakers at the last flight of the day to shut the oil shut off valves on the E models this would keep the oil from flooding the turbine section.. The breakers was pulled to keep the prop from feathering while pulling the fire handle to shut the oil valve off... We did this if some one still had external, or gtc, power on.. Quote Link to comment Share on other sites More sharing options...
GVS Posted January 26, 2010 Share Posted January 26, 2010 John Wilson's reply is as I remember it on A models. Quote Link to comment Share on other sites More sharing options...
GVS Posted January 26, 2010 Share Posted January 26, 2010 Without AC power on the acft. there is no way the prop will feather. The prop feather motor runs on three phase AC. Correct.True on E2C and probably P3 as well Quote Link to comment Share on other sites More sharing options...
John H Wilson Posted January 26, 2010 Share Posted January 26, 2010 I never worked on A's... This was on the E's (62s) when I worked on them.. Quote Link to comment Share on other sites More sharing options...
larry myers Posted January 26, 2010 Share Posted January 26, 2010 We use to pull those breakers at the last flight of the day to shut the oil shut off valves on the E models this would keep the oil from flooding the turbine section.. The breakers was pulled to keep the prop from feathering while pulling the fire handle to shut the oil valve off... We did this if some one still had external, or gtc, power on.. At the end of the flying day the way I closed the oil tank so valve was to pull the T handle with only DC power on the acft. This precluded unnecessarly exercising the prop feather motors. With the valve closed would then pull the oil tank so valve cbs. I did this for the most part so as to preclude having to service engine oil right away when I really wanted to get on with the post flight/recovery. However, as you say this also prevents oil from leaking into the power section if there is a leaky check valve, a not uncommon occurance. The best part was I could service eng. oil the next morning at my leisure after which would reset the so valve cbs. On more than one instance took grief from flt. line supervision when they saw me servicing oil knowing the bird had landed the previous evening. Quote Link to comment Share on other sites More sharing options...
John H Wilson Posted January 26, 2010 Share Posted January 26, 2010 I remember when I was stationed at Pope (69-73) the crew started all 4 engines for their mission, and the FE did not notice the c/bs pulled on the oil shut off valves... you know the rest of the story.. Quote Link to comment Share on other sites More sharing options...
RZHill Posted January 26, 2010 Share Posted January 26, 2010 Don't think you could get to #2 before 3&4 locked up. This FE should be shot, and the instructor that trained him with him!!! RZ A's used 3 phase ac to feather the prop also. Dc is the control , ac is the operator. Quote Link to comment Share on other sites More sharing options...
EClark Posted January 26, 2010 Share Posted January 26, 2010 I have had as many as three check valves at one time that leaked back you learn real quick how to take care of that problem. Quote Link to comment Share on other sites More sharing options...
GVS Posted January 26, 2010 Share Posted January 26, 2010 Don't think you could get to #2 before 3&4 locked up. This FE should be shot, and the instructor that trained him with him!!! RZ A's used 3 phase ac to feather the prop also. Dc is the control , ac is the operator.The crew chief should have reset the C/B's before the FE set foot on the aircraft! Quote Link to comment Share on other sites More sharing options...
EClark Posted January 26, 2010 Share Posted January 26, 2010 I agree with that We always reset the C/B way before the flight crew got to the plane. I always ran the props through the cycle. Quote Link to comment Share on other sites More sharing options...
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