Hughes 269/Schweizer 300 series
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The reason there is no lateral CG published for the 269A is regulatory. The 269A was first certified under CAR/CAM 6, Rotorcraft Airworhtiness; Normal Category. These were older and vastly different certification regulations than FAR Part 27 used today. You must read the entire CAR/CAM6 to fully understand the interelationship between the various regulations but a very superficial answer can be provided using those most pertinant to this discussion.
CAM 6.101 pertained to weight limitations. The maximum and minimum weights at which the rotorcraft will be suitable for operation is established according to the rules. The maximum weight is based on a 170 pound person in each seat. The minimum is a single 170 pound person which is the minimum necessary to operate the 269A.
CG limitations could be found in 6.102. In that regulatory era, CG limitations were based on the aircraft minimum and maximum weights for which the aircraft was intended to be operated and had to be established for the most forward and aft permission for each weight. Loading instructions were only required to be provided if the center of gravity position under any possible loading condition between the maximum and minimum weights in 6.101, with assumed weights for individual passengers and crewmembers variable over the anticipated range of such weights, lies beyond:
1. The extremes selected by the applicant,
2. the extremes for which the structure has been proven,
3. The extremes for which compliance with all of the applicable flight requirements has been demonstrated.
CAR 6.740 defines what information shall be furnished in the Rotorcraft Flight Manual. For weight and loading distribution it states that the rotorcraft weights and center of gravity limits required by sections 6.101 and 6.102 shall be included. CAR 6.716 says essentially the same thing. Where the variety of possible loading conditions warrants, instructions shall be included to facilitate observance of the limitations. The 269A was not required to publish specific lateral limits if all applicable flight requirements could be demonstrated and no structrual limits were exceeded when there was a 170 pound person in each seat.
Simply stated, lateral CG limits could not be exceeded in the 269A when the aircraft was operated within the approved limits using a weight of 170 pounds for passengers and pilots; therefore the regulations at the time the aircraft was first certificated did not require Hughes to publish lateral limits.
Longitudinal limits were required to be established by regulation so they are provided in the flight manual.
The 269B and 269C were certificated as modifications to the original type certificate for the 269A so were not required to meet the additional requirements imposed by FAR Part 27.
When you read CAR/CAM 6 you will find many arbitrary standards used for design and performance. For instance in 6.353 controls had to be located and arranged for full and unrestricted movement for individuals ranging from 5'2" to 6'0". If you were shorter or taller the controls were never designed for you since the regulations did not require them to be so designed. You might be suprised to learn that controls could be certified for forces of 130 pound in the pedals and 100 pounds fore and aft and 67 pounds laterally for the cyclic. Imagine the complaints!
In days gone by there were fewer regulations and pilots relied more on common sense, judgement and experience. I don't mean to argue that hard regulations for weight and CG has not improved safety over the years, but it has limited the usefulness of rotorcraft. You do not need to be a test pilot or an engineer to know when you are near the limit of lateral cyclic travel. You know that when you begin the lift to a hover and before the skids ever fully leave the ground. Common sense dictates that if there is a half an inch of lateral cyclic margin remaining you might be a little heavy on the opposite side and should consider doing something about it. Nevertheless, I have conducted flight testing in the TH-55A, H269A, H269B, and H269C at lateral CG limits of 2.0. This was acheived using weight bags attached to the outside of the helicopter since it was often not possible to put enough weight inside.
CAM 6.101 pertained to weight limitations. The maximum and minimum weights at which the rotorcraft will be suitable for operation is established according to the rules. The maximum weight is based on a 170 pound person in each seat. The minimum is a single 170 pound person which is the minimum necessary to operate the 269A.
CG limitations could be found in 6.102. In that regulatory era, CG limitations were based on the aircraft minimum and maximum weights for which the aircraft was intended to be operated and had to be established for the most forward and aft permission for each weight. Loading instructions were only required to be provided if the center of gravity position under any possible loading condition between the maximum and minimum weights in 6.101, with assumed weights for individual passengers and crewmembers variable over the anticipated range of such weights, lies beyond:
1. The extremes selected by the applicant,
2. the extremes for which the structure has been proven,
3. The extremes for which compliance with all of the applicable flight requirements has been demonstrated.
CAR 6.740 defines what information shall be furnished in the Rotorcraft Flight Manual. For weight and loading distribution it states that the rotorcraft weights and center of gravity limits required by sections 6.101 and 6.102 shall be included. CAR 6.716 says essentially the same thing. Where the variety of possible loading conditions warrants, instructions shall be included to facilitate observance of the limitations. The 269A was not required to publish specific lateral limits if all applicable flight requirements could be demonstrated and no structrual limits were exceeded when there was a 170 pound person in each seat.
Simply stated, lateral CG limits could not be exceeded in the 269A when the aircraft was operated within the approved limits using a weight of 170 pounds for passengers and pilots; therefore the regulations at the time the aircraft was first certificated did not require Hughes to publish lateral limits.
Longitudinal limits were required to be established by regulation so they are provided in the flight manual.
The 269B and 269C were certificated as modifications to the original type certificate for the 269A so were not required to meet the additional requirements imposed by FAR Part 27.
When you read CAR/CAM 6 you will find many arbitrary standards used for design and performance. For instance in 6.353 controls had to be located and arranged for full and unrestricted movement for individuals ranging from 5'2" to 6'0". If you were shorter or taller the controls were never designed for you since the regulations did not require them to be so designed. You might be suprised to learn that controls could be certified for forces of 130 pound in the pedals and 100 pounds fore and aft and 67 pounds laterally for the cyclic. Imagine the complaints!
In days gone by there were fewer regulations and pilots relied more on common sense, judgement and experience. I don't mean to argue that hard regulations for weight and CG has not improved safety over the years, but it has limited the usefulness of rotorcraft. You do not need to be a test pilot or an engineer to know when you are near the limit of lateral cyclic travel. You know that when you begin the lift to a hover and before the skids ever fully leave the ground. Common sense dictates that if there is a half an inch of lateral cyclic margin remaining you might be a little heavy on the opposite side and should consider doing something about it. Nevertheless, I have conducted flight testing in the TH-55A, H269A, H269B, and H269C at lateral CG limits of 2.0. This was acheived using weight bags attached to the outside of the helicopter since it was often not possible to put enough weight inside.
Anyone interested in sharing a 300C
Is anyone interested in forming a small syndicate to buy / lease a 300C / CBI in Norfolk ?
If anyones selling a good example of the type then happy
to hear from you either on here or PM me please.
Thanks
BG
If anyones selling a good example of the type then happy
to hear from you either on here or PM me please.Thanks
BG
Join Date: Jul 2009
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Hughes 269A slow cranking with starter
Hi
I have a problem with my Hughes 269A starter; it turns the engine very slowly. The starter motor has been checked by a shop and they did not find any problem with it. The starter battery is from a truck with plenty of power. I have tested to connect the battery to the motor with jumper cables to exclude possible problem with the relay and ground cable without success. As you can see and hear in my video clip on youtube.com the engine kicks-back for each turn of the engine. Ignition and fuel are cut of during this clip. It is a 12 volt system
I have checked the timing too, it was correct. What if the work-shop are wrong about the starter motor ? They said that they open it up and had a visual inspection and there was notning wrong about it. Could it be that the starter output tourque are to low. It is a very old starter. What brand of starter motor is it on new Hughes 300 ?
Please advice
I have a problem with my Hughes 269A starter; it turns the engine very slowly. The starter motor has been checked by a shop and they did not find any problem with it. The starter battery is from a truck with plenty of power. I have tested to connect the battery to the motor with jumper cables to exclude possible problem with the relay and ground cable without success. As you can see and hear in my video clip on youtube.com the engine kicks-back for each turn of the engine. Ignition and fuel are cut of during this clip. It is a 12 volt system
I have checked the timing too, it was correct. What if the work-shop are wrong about the starter motor ? They said that they open it up and had a visual inspection and there was notning wrong about it. Could it be that the starter output tourque are to low. It is a very old starter. What brand of starter motor is it on new Hughes 300 ?
Please advice
Last edited by Senior Pilot; 21st Jul 2009 at 21:26. Reason: embed YouTube link
Doesnt sound any different to any of my 3 300's. You have a high torque starter motor on it ( normally sound like that) could try a Kelly areospace high speed starter which turns the engine over very quickly. Is the engine not starting ? In which case have the starting vibrators checked these give a shower of sparks to help start if the contacts are not good you will have a problem
Have you cleaned the earth strap which normally goes to the cluster on the left side of the aircraft ?
Have you cleaned the earth strap which normally goes to the cluster on the left side of the aircraft ?
Your cables from accu are very THIN
better use more profile of thick cables,
"welding" cables are great for that,
DC voltage on high consumption like on start up
drops voltage drastically.....
better use more profile of thick cables,
"welding" cables are great for that,
DC voltage on high consumption like on start up
drops voltage drastically.....
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They said that they open it up and had a visual inspection and there was notning wrong about it
Good luck!
Not a 24V starter is it? Later 300's are 24V.
12V is MZ-4226 (LW 18989)
24V is MHB-4020 (LW 18990)
Kelly Aerospace Power Systems
Aftermarket and STC equivalents will be different of course.
Just watched your tube clip. Sounds about right to me.
12V is MZ-4226 (LW 18989)
24V is MHB-4020 (LW 18990)
Kelly Aerospace Power Systems
Aftermarket and STC equivalents will be different of course.
Just watched your tube clip. Sounds about right to me.
Last edited by RVDT; 22nd Jul 2009 at 12:41. Reason: Additional info
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Not only is it cranking slowly, but the kickback is very noticeable....this will damage the starter pinion and the flywheel ring-gear....as soon as the starter starts spinning, you are giving a mighty blow in the opposite direction.
PLEASE NOTE I am not an Aviation mechanic but DO have a wide experience of 2-strokes and 4-strokes, petrol and diesel and petrol-paraffin
Connect a volt-meter (a cheap multimeter will suffice) between the battery-lead terminal on the starter and an earth-point......a fully-charged 12 volt battery should give a shade over 14 volts........crank the starter and it should hold 10 volts.....lower and you are looking for excessive current-draw or high resistance in the feed or return or a battery with high internal resistance.
Are the leads getting hot?....if yes, high current draw.....starter could have shorted field, field down to earth,a weak brush-spring or a lot of conductive brush-dust tracking it down (very unlikely that the starter is faulty as any decent engineer would have checked the brushes and blown out with an airline.)
As has been suggested, you MIGHT have a 24V starter on a 12V system....this would turn the engine very slowly......your ignition-advance at cranking -speed should NOT kick-back,but should be retarded enough that the combustion pressure builds AFTER top dead centre, pushing the piston down......if it's too advanced, the pressure will oppose the up-coming piston and can stop it dead, and even reverse it's direction as seen in your video.
That is extreme cruelty to machinery and you should be prosecuted
(you will have your wallet lightened with the repair-costs ,anyway! )
After the war, many old cars were converted to 12Volt from 6....it was common to leave the 6-volt starter in place....took a hellish current but spun the engine mega-fast....the start was so quick that overheating wasn't a problem!
PLEASE NOTE I am not an Aviation mechanic but DO have a wide experience of 2-strokes and 4-strokes, petrol and diesel and petrol-paraffin
Connect a volt-meter (a cheap multimeter will suffice) between the battery-lead terminal on the starter and an earth-point......a fully-charged 12 volt battery should give a shade over 14 volts........crank the starter and it should hold 10 volts.....lower and you are looking for excessive current-draw or high resistance in the feed or return or a battery with high internal resistance.
Are the leads getting hot?....if yes, high current draw.....starter could have shorted field, field down to earth,a weak brush-spring or a lot of conductive brush-dust tracking it down (very unlikely that the starter is faulty as any decent engineer would have checked the brushes and blown out with an airline.)
As has been suggested, you MIGHT have a 24V starter on a 12V system....this would turn the engine very slowly......your ignition-advance at cranking -speed should NOT kick-back,but should be retarded enough that the combustion pressure builds AFTER top dead centre, pushing the piston down......if it's too advanced, the pressure will oppose the up-coming piston and can stop it dead, and even reverse it's direction as seen in your video.
That is extreme cruelty to machinery and you should be prosecuted
(you will have your wallet lightened with the repair-costs ,anyway! )
After the war, many old cars were converted to 12Volt from 6....it was common to leave the 6-volt starter in place....took a hellish current but spun the engine mega-fast....the start was so quick that overheating wasn't a problem!
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Hughes 500
It´s surprise me that all 300 sounds like mine. No it is not a high torque motor, it is a 12 V Prestolite starter. I was a builder and owner of Van´s RV6 with a Lyc O-360 for many years and that starter motor was turning the prop much faster. I´m able to start the engine but the starter drains the battery very quickly.
9Aplus
I will check the Voltage drop
that chinese fella
I agree with you but the shop had no equipment to mesure the tourque.
RVDT
12V is MZ-4226 (LW 18989)
Kely Aerospace Power System
Okay, I will check prices.
pitot212
I agree, It sound like a 24V starter being used on a 12V system, BUT it is not. It´s a 12 V starter in a 12 V system.
I have a new question
Do anyone have experiance of starter motors made by B&C or SKY-TEC?
It´s surprise me that all 300 sounds like mine. No it is not a high torque motor, it is a 12 V Prestolite starter. I was a builder and owner of Van´s RV6 with a Lyc O-360 for many years and that starter motor was turning the prop much faster. I´m able to start the engine but the starter drains the battery very quickly.
9Aplus
I will check the Voltage drop
that chinese fella
I agree with you but the shop had no equipment to mesure the tourque.
RVDT
12V is MZ-4226 (LW 18989)
Kely Aerospace Power System
Okay, I will check prices.
pitot212
I agree, It sound like a 24V starter being used on a 12V system, BUT it is not. It´s a 12 V starter in a 12 V system.
I have a new question
Do anyone have experiance of starter motors made by B&C or SKY-TEC?
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300 share for sale ebay
There is currently a 300/269 share for sale in Gloucester if I was interrested in this what should I look out for .( I have no experience of helicopters ,looked like a cheap way of doing my training)
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New M/R driveshaft for the 300c
Hello dear friends
Any one knows how much the new M/R driveshaft for the 300C with the increased lifetime(3100 or 3500 hours) will cost ?
Thank you very much !
Any one knows how much the new M/R driveshaft for the 300C with the increased lifetime(3100 or 3500 hours) will cost ?
Thank you very much !
Join Date: Feb 2008
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