I have be practicing with the FS2000 SR20 C model with the EHSI. I notice that when I fly a heading that is the reciprocal of the OBS setting I still fly toward the “needle” rather than away. Does the real Sandel on the SR20 work that way?
It’s been a long time since I used an HSI regularly, but as I remember one of its chief benefits is that there is no such thing as reverse sensing when tracking a VOR. What you see is what you get. (You can get reverse sensing when tracking a localizer though, if you don’t have the HSI set up right.)
It has to do with the fact that the “CDI” part of the HSI revolves when the OBS knob is turned. (You wouldn’t get reverse sensing with a CDI either, if you could pull it out and rotate it 180 degrees when on a reciprocal of the OBS heading.)
Joe
I have be practicing with the FS2000 SR20 C model with the EHSI. I notice that when I fly a heading that is the reciprocal of the OBS setting I still fly toward the “needle” rather than away. Does the real Sandel on the SR20 work that way?
A slight correction to my previous post: Actually, it’s more to the point to say that the “CDI” portion of the HSI rotates with the compass card. (Though it does rotate with the OBS knob too.) Corrected post below.
It’s been a long time since I used an HSI regularly, but as I remember one of its chief benefits is that there is no such thing as reverse sensing when tracking a VOR. What you see is what you get. (You can get reverse sensing when tracking a localizer though, if you don’t have the HSI set up right.)
It has to do with the fact that the “CDI” part of the HSI revolves with the compass card. (You wouldn’t get reverse sensing with a CDI either, if you could pull it out of the panel, rotate it 180 degrees, and push it back in when on a reciprocal of the OBS heading.)
Joe
I have be practicing with the FS2000 SR20 C model with the EHSI. I notice that when I fly a heading that is the reciprocal of the OBS setting I still fly toward the “needle” rather than away. Does the real Sandel on the SR20 work that way?
A slight correction to my previous post: Actually, it’s more to the point to say that the “CDI” portion of the HSI rotates with the compass card. (Though it does rotate with the OBS knob too.) Corrected post below.
Now I understand. Boy you can really get spoiled with that. Set the inbound course and you can fly outbound without playing mental games and a quick glance at the HSI tells you weather you are inbound or outbound. On interception you don’t subtract or add 45 to the course to get an interception angle. That is why I stopped using the SR20 model on the FS2000. When out SR20 comes I will use GPS, autopilot, and anything else that will make flying easier, but when I fly FS2000 I fly a 182RG without autopilot and with random instrument failures. I figure it will be easier to go from something complex to something simple then the other way around. Although I did notice the SR20 model is harder to slow down.
You can’t appreciate how spoiled spoiled really is until you fly a localizer backcourse approach with either the Sandel or a conventional HSI. No reverse sensing. Just remember to set the course pointer to the front course inbound and all will be well.
J. Seckler
A slight correction to my previous post: Actually, it’s more to the point to say that the “CDI” portion of the HSI rotates with the compass card. (Though it does rotate with the OBS knob too.) Corrected post below.
Now I understand. Boy you can really get spoiled with that. Set the inbound course and you can fly outbound without playing mental games and a quick glance at the HSI tells you weather you are inbound or outbound. On interception you don’t subtract or add 45 to the course to get an interception angle. That is why I stopped using the SR20 model on the FS2000. When out SR20 comes I will use GPS, autopilot, and anything else that will make flying easier, but when I fly FS2000 I fly a 182RG without autopilot and with random instrument failures. I figure it will be easier to go from something complex to something simple then the other way around. Although I did notice the SR20 model is harder to slow down.
You can’t appreciate how spoiled spoiled really is until you fly a localizer backcourse approach with either the Sandel or a conventional HSI. No reverse sensing. Just remember to set the course pointer to the front course inbound and all will be well.
J. Seckler
Like all things, nothing is quite so simple. With the 430, unless you like to work hard, you are flying in GPS mode until you turn inbound (and a few other predicates are satisfied) at which point the 430 will switch to VLOC mode. For instance, when flying an ILS full procedure (with course reversal) you will be in GPS mode until you are inbound and close to the FAF. On the outbound part of the procedure the GPS will continue to be forward sensing (and the annunciated DTK will be in the outbound direction, and the course needle should point outbound) whereas if you were tracking the localizer outbound you would have the course needle pointing inbound to get correct sensing.
I’ll have to go back to the sim and figure out what 430 does on BC approaches (in particular, what the DTK inbound on the backcourse would be.)
You also need to hit the REV button on your autopilot when the needle is reverse sensing, since it needs to know that it should be flying the course opposite the pointer (and with the needle deviation reversed.)
Backcourse approaches are the spawn of the devil. If there’s a GPS approach to the same runway as the LOC BC approach, it’ll be easier to fly (and the MDAs ought to be about the same.)
I agree that if you use GPS guidance and have to fly a procedure turn it is more complicated. In the areas I fly procedure turns are extremely uncommon (I can’t remember the last time I had to fly one) and vectors are the norm. I almost always hand fly approaches and had flying a back course is made much easier with a HSI. I agree that if you have George do it then you have to push the REV button. On the 430 for a BC appraoch I would load and activate the approach, switch to VOR/LOC mode and fly the needle. It’s fun!
J. Seckler
You can’t appreciate how spoiled spoiled really is until you fly a localizer backcourse approach with either the Sandel or a conventional HSI. No reverse sensing. Just remember to set the course pointer to the front course inbound and all will be well.
J. Seckler
Like all things, nothing is quite so simple. With the 430, unless you like to work hard, you are flying in GPS mode until you turn inbound (and a few other predicates are satisfied) at which point the 430 will switch to VLOC mode. For instance, when flying an ILS full procedure (with course reversal) you will be in GPS mode until you are inbound and close to the FAF. On the outbound part of the procedure the GPS will continue to be forward sensing (and the annunciated DTK will be in the outbound direction, and the course needle should point outbound) whereas if you were tracking the localizer outbound you would have the course needle pointing inbound to get correct sensing.
I’ll have to go back to the sim and figure out what 430 does on BC approaches (in particular, what the DTK inbound on the backcourse would be.)
You also need to hit the REV button on your autopilot when the needle is reverse sensing, since it needs to know that it should be flying the course opposite the pointer (and with the needle deviation reversed.)
Backcourse approaches are the spawn of the devil. If there’s a GPS approach to the same runway as the LOC BC approach, it’ll be easier to fly (and the MDAs ought to be about the same.)